The N42 and N46 are the four-cylinder petrol engines that brought Valvetronic to BMW's smaller cars. They powered the E46 316i, 318i and 320i, the E87 118i and 120i, the E90 318i and 320i, the E83 X3 2.0i and the Z4 2.0i.
This guide also covers the N40 and N45, the 1.6 litre versions without Valvetronic. These engines are economical but are known for oil consumption and timing chain wear, so a careful check is essential.
- Production: 2001–2012
- Versions covered: N42B18, N40B16, N42B20, N46B18, N45B16, N46B20 and N45B20S
- Output range: 115–173 hp
- Fuel and layout: petrol inline-4
- Fitted to: 13 BMW models across 5 chassis generations
- In our stock now: ask the desk for the next arrival — browse all N42 and N46 engines
The N42 and N46 at a glance
The table lists every N42 and N46 version we supply with its capacity, layout, output and production years. Use it with your car's engine code to find the right unit.
| Engine code | Capacity | Layout | Power | Torque | Years |
|---|---|---|---|---|---|
| N42B18 | 1.8 L | Inline-4, naturally aspirated | 115 hp | 175 Nm | 2001–2004 |
| N40B16 | 1.6 L | Inline-4, naturally aspirated | 116 hp | 150 Nm | 2001–2004 |
| N42B20 | 2.0 L | Inline-4, naturally aspirated | 143 hp | 200 Nm | 2001–2004 |
| N46B18 | 1.8 L | Inline-4, naturally aspirated | 115 hp | 175 Nm | 2004–2007 |
| N45B16 | 1.6 L | Inline-4, naturally aspirated | 116 hp | 150 Nm | 2004–2011 |
| N46B20 | 2.0 L | Inline-4, naturally aspirated | 150 hp | 200 Nm | 2004–2012 |
| N45B20S | 2.0 L | Inline-4, naturally aspirated | 173 hp | 200 Nm | 2005–2007 |
Across 7 versions, output runs from 115 to 173 hp. The spread reflects different capacities, tuning for different markets and the technical updates BMW made over 12 years of production.
History of the N42 and N46
BMW introduced the N42 in 2001 with Valvetronic, double VANOS and balance shafts. The N46 replaced it from 2004 with revisions to the head and engine management, and the N46N followed in 2007. The N43 and N13 eventually took over.
2001: the N42B18 arrived with 1.8 L and 115 hp in the BMW E46 316i and BMW E46 Compact.
2001: the N40B16 arrived with 1.6 L and 116 hp in the BMW E46 316i and BMW E46 316ti. Compared with the N42B18, it added 1 hp.
2001: the N42B20 arrived with 2.0 L and 143 hp in the BMW E46 318i. Compared with the N40B16, it added 27 hp.
2004: the N46B18 arrived with 1.8 L and 115 hp in the BMW E87 316i and BMW E90 316i. It was a lower-output version for smaller or more economical models.
2004: the N45B16 arrived with 1.6 L and 116 hp in the BMW E90 316i and BMW E87 116i. Compared with the N46B18, it added 1 hp.
2004: the N46B20 arrived with 2.0 L and 150 hp in the BMW E90 318i, BMW E87 118i and BMW E60 520i. Compared with the N45B16, it added 34 hp.
2005: the N45B20S arrived with 2.0 L and 173 hp in the BMW E90 320si and BMW E87 120i. Compared with the N46B20, it added 23 hp.
Every N42 and N46 version explained
N42B18 (1.8 L, 115 hp)
Built from 2001 to 2004, the N42B18 displaces 1.8 L in an inline-4 layout and is naturally aspirated. It produces 115 hp and 175 Nm on petrol. That is about 64 hp and 97 Nm per litre, a relaxed tune aimed at torque, durability and economy. Within the N42 and N46 family, the N40B16 (116 hp), N42B20 (143 hp) and N45B16 (116 hp) are more powerful. It was fitted to the BMW E46 316i and BMW E46 Compact.
Reading the code: N marks an N-series code, the generation of BMW engines introduced from 2001; 42 is the family number; B stands for petrol (from the German Benzin); 18 is the capacity in decilitres, so 1.8 litres.
N40B16 (1.6 L, 116 hp)
N40B16: 1.6 L, inline-4, petrol, naturally aspirated. Output is 116 hp with 150 Nm of torque, and production ran from 2001 to 2004. That is about 73 hp and 94 Nm per litre, a relaxed tune aimed at torque, durability and economy. Within the N42 and N46 family, the N42B20 (143 hp), N46B20 (150 hp) and N45B20S (173 hp) are more powerful, while the N42B18 (115 hp) and N46B18 (115 hp) are milder. It was fitted to the BMW E46 316i and BMW E46 316ti.
Reading the code: N marks an N-series code, the generation of BMW engines introduced from 2001; 40 is the family number; B stands for petrol (from the German Benzin); 16 is the capacity in decilitres, so 1.6 litres.
N42B20 (2.0 L, 143 hp)
Built from 2001 to 2004, the N42B20 displaces 2.0 L in an inline-4 layout and is naturally aspirated. It produces 143 hp and 200 Nm on petrol. That is about 72 hp and 100 Nm per litre, a relaxed tune aimed at torque, durability and economy. Within the N42 and N46 family, the N46B20 (150 hp) and N45B20S (173 hp) are more powerful, while the N42B18 (115 hp), N40B16 (116 hp) and N46B18 (115 hp) are milder. It was fitted to the BMW E46 318i.
Reading the code: N marks an N-series code, the generation of BMW engines introduced from 2001; 42 is the family number; B stands for petrol (from the German Benzin); 20 is the capacity in decilitres, so 2.0 litres.
N46B18 (1.8 L, 115 hp)
The N46B18 is a 1.8 L inline-4 petrol engine, naturally aspirated, rated at 115 hp and 175 Nm. BMW built it from 2004 to 2007. That is about 64 hp and 97 Nm per litre, a relaxed tune aimed at torque, durability and economy. Within the N42 and N46 family, the N40B16 (116 hp), N42B20 (143 hp) and N45B16 (116 hp) are more powerful. It was fitted to the BMW E87 316i and BMW E90 316i.
Reading the code: N marks an N-series code, the generation of BMW engines introduced from 2001; 46 is the family number; B stands for petrol (from the German Benzin); 18 is the capacity in decilitres, so 1.8 litres.
N45B16 (1.6 L, 116 hp)
The N45B16 is a 1.6 L inline-4 petrol engine, naturally aspirated, rated at 116 hp and 150 Nm. BMW built it from 2004 to 2011. That is about 73 hp and 94 Nm per litre, a relaxed tune aimed at torque, durability and economy. Within the N42 and N46 family, the N42B20 (143 hp), N46B20 (150 hp) and N45B20S (173 hp) are more powerful, while the N42B18 (115 hp) and N46B18 (115 hp) are milder. It was fitted to the BMW E90 316i and BMW E87 116i.
Reading the code: N marks an N-series code, the generation of BMW engines introduced from 2001; 45 is the family number; B stands for petrol (from the German Benzin); 16 is the capacity in decilitres, so 1.6 litres.
N46B20 (2.0 L, 150 hp)
Built from 2004 to 2012, the N46B20 displaces 2.0 L in an inline-4 layout and is naturally aspirated. It produces 150 hp and 200 Nm on petrol. That is about 75 hp and 100 Nm per litre, a strong figure for a road engine of its era. Within the N42 and N46 family, the N45B20S (173 hp) is more powerful, while the N42B18 (115 hp), N40B16 (116 hp) and N42B20 (143 hp) are milder. It was fitted to the BMW E90 318i, BMW E87 118i, BMW E60 520i and BMW E84 X1 18i. See every N46B20 in stock.
Reading the code: N marks an N-series code, the generation of BMW engines introduced from 2001; 46 is the family number; B stands for petrol (from the German Benzin); 20 is the capacity in decilitres, so 2.0 litres.
N45B20S (2.0 L, 173 hp)
Built from 2005 to 2007, the N45B20S displaces 2.0 L in an inline-4 layout and is naturally aspirated. It produces 173 hp and 200 Nm on petrol. That is about 87 hp and 100 Nm per litre, a strong figure for a road engine of its era. Within the N42 and N46 family, it is the most powerful version, while the N42B18 (115 hp), N40B16 (116 hp) and N42B20 (143 hp) are milder. It was fitted to the BMW E90 320si and BMW E87 120i.
Reading the code: N marks an N-series code, the generation of BMW engines introduced from 2001; 45 is the family number; B stands for petrol (from the German Benzin); 20 is the capacity in decilitres, so 2.0 litres; S identifies the version or output stage.
Which cars use the N42 and N46
The N42 and N46 was fitted to 13 models. The list below is grouped by chassis generation so you can find your car quickly. Always confirm the exact code with your VIN, because BMW often used more than one engine in the same model.
BMW E46 fourth 3 Series (1997–2006)
In the fourth 3 Series, built 1997–2006 as a saloon, Touring, coupé, convertible, Compact, the N42 and N46 powered the 316i (N42B18, 115 hp), Compact (N42B18, 115 hp), 316i (N40B16, 116 hp), 316ti (N40B16, 116 hp) and 318i (N42B20, 143 hp).
For an E46, confirm the production date as well as the model: BMW often changed engine versions at the mid-life update. All E46 engines in stock.
The 316i uses the N42B18. BMW 316i engines for sale.
The 316i uses the N40B16. BMW 316i engines for sale.
The 318i uses the N42B20. BMW 318i engines for sale.
BMW E87 first 1 Series five-door (2004–2011)
In the first 1 Series five-door, built 2004–2011 as a hatchback, the N42 and N46 powered the 316i (N46B18, 115 hp), 116i (N45B16, 116 hp), 118i (N46B20, 150 hp) and 120i (N45B20S, 173 hp).
For an E87, confirm the production date as well as the model: BMW often changed engine versions at the mid-life update. All E87 engines in stock.
The 316i uses the N46B18. BMW 316i engines for sale.
The 116i uses the N45B16. BMW 116i engines for sale.
The 118i uses the N46B20. BMW 118i engines for sale.
The 120i uses the N45B20S. BMW 120i engines for sale.
BMW E90 fifth 3 Series saloon (2005–2012)
In the fifth 3 Series saloon, built 2005–2012 as a saloon, the N42 and N46 powered the 316i (N46B18, 115 hp), 316i (N45B16, 116 hp), 318i (N46B20, 150 hp) and 320si (N45B20S, 173 hp).
For an E90, confirm the production date as well as the model: BMW often changed engine versions at the mid-life update. All E90 engines in stock.
The 316i uses the N46B18. BMW 316i engines for sale.
The 316i uses the N45B16. BMW 316i engines for sale.
The 318i uses the N46B20. BMW 318i engines for sale.
BMW E60 fifth 5 Series (2003–2010)
In the fifth 5 Series, built 2003–2010 as a saloon, the N42 and N46 powered the 520i (N46B20, 150 hp).
When ordering for an E60, check whether the car is rear-drive or xDrive and whether it has a manual or automatic gearbox, because the sump and flywheel can differ. All E60 engines in stock.
The 520i uses the N46B20. BMW 520i engines for sale.
BMW E84 first X1 (2009–2015)
In the first X1, built 2009–2015 as an SAV, the N42 and N46 powered the X1 18i (N46B20, 150 hp).
The quickest way to confirm the right N42 and N46 for your E84 is to send us the VIN; we check the engine code, the gearbox and the drive type. All E84 engines in stock.
The X1 18i uses the N46B20. BMW X1 engines for sale.
Will an N42 and N46 fit my BMW? Model-by-model answers
Short answers for every model that left the factory with an N42 and N46, with prices from our current stock.
Will the N42B18 fit my BMW E46 316i?
For the BMW E46 316i, the N42B18 is the factory engine and the one to order. The fourth 3 Series was built 1997–2006, and the N42B18 was produced 2001–2004, so check that your car's build date falls inside that window. Confirm the drive type (rear-drive or xDrive), the gearbox (manual or automatic) and the emissions standard, because these can change the sump, the flywheel and the software. Send us the VIN and we check all of it for you.
How much is a replacement engine for a BMW E46 316i?
We do not have an N42B18 on the shelf for the E46 316i at the moment. Units arrive regularly; send us your VIN and we will tell you when the next one is ready and what it will cost, including delivery.
Will the N42B18 fit my BMW E46 Compact?
For the BMW E46 Compact, the N42B18 is the factory engine and the one to order. The fourth 3 Series was built 1997–2006, and the N42B18 was produced 2001–2004, so check that your car's build date falls inside that window. Confirm the drive type (rear-drive or xDrive), the gearbox (manual or automatic) and the emissions standard, because these can change the sump, the flywheel and the software. Send us the VIN and we check all of it for you.
How much is a replacement engine for a BMW E46 Compact?
We do not have an N42B18 on the shelf for the E46 Compact at the moment. Units arrive regularly; send us your VIN and we will tell you when the next one is ready and what it will cost, including delivery.
Will the N40B16 fit my BMW E46 316i?
Yes, the BMW E46 316i left the factory with the N40B16, so an N40B16 from another car is the direct replacement. The fourth 3 Series was built 1997–2006, and the N40B16 was produced 2001–2004, so check that your car's build date falls inside that window. Confirm the drive type (rear-drive or xDrive), the gearbox (manual or automatic) and the emissions standard, because these can change the sump, the flywheel and the software. Send us the VIN and we check all of it for you.
How much is a replacement engine for a BMW E46 316i?
We do not have an N40B16 on the shelf for the E46 316i at the moment. Units arrive regularly; send us your VIN and we will tell you when the next one is ready and what it will cost, including delivery.
Will the N40B16 fit my BMW E46 316ti?
Yes, the BMW E46 316ti left the factory with the N40B16, so an N40B16 from another car is the direct replacement. The fourth 3 Series was built 1997–2006, and the N40B16 was produced 2001–2004, so check that your car's build date falls inside that window. Confirm the drive type (rear-drive or xDrive), the gearbox (manual or automatic) and the emissions standard, because these can change the sump, the flywheel and the software. Send us the VIN and we check all of it for you.
How much is a replacement engine for a BMW E46 316ti?
We do not have an N40B16 on the shelf for the E46 316ti at the moment. Units arrive regularly; send us your VIN and we will tell you when the next one is ready and what it will cost, including delivery.
Will the N42B20 fit my BMW E46 318i?
The N42B20 is the original engine for the BMW E46 318i, which makes it the straightforward choice. The fourth 3 Series was built 1997–2006, and the N42B20 was produced 2001–2004, so check that your car's build date falls inside that window. Confirm the drive type (rear-drive or xDrive), the gearbox (manual or automatic) and the emissions standard, because these can change the sump, the flywheel and the software. Send us the VIN and we check all of it for you.
How much is a replacement engine for a BMW E46 318i?
We do not have an N42B20 on the shelf for the E46 318i at the moment. Units arrive regularly; send us your VIN and we will tell you when the next one is ready and what it will cost, including delivery.
Will the N46B18 fit my BMW E87 316i?
The N46B18 is the original engine for the BMW E87 316i, which makes it the straightforward choice. The first 1 Series five-door was built 2004–2011, and the N46B18 was produced 2004–2007, so check that your car's build date falls inside that window. Confirm the drive type (rear-drive or xDrive), the gearbox (manual or automatic) and the emissions standard, because these can change the sump, the flywheel and the software. Send us the VIN and we check all of it for you.
How much is a replacement engine for a BMW E87 316i?
We do not have an N46B18 on the shelf for the E87 316i at the moment. Units arrive regularly; send us your VIN and we will tell you when the next one is ready and what it will cost, including delivery.
Will the N46B18 fit my BMW E90 316i?
The N46B18 is the original engine for the BMW E90 316i, which makes it the straightforward choice. The fifth 3 Series saloon was built 2005–2012, and the N46B18 was produced 2004–2007, so check that your car's build date falls inside that window. Confirm the drive type (rear-drive or xDrive), the gearbox (manual or automatic) and the emissions standard, because these can change the sump, the flywheel and the software. Send us the VIN and we check all of it for you.
How much is a replacement engine for a BMW E90 316i?
We do not have an N46B18 on the shelf for the E90 316i at the moment. Units arrive regularly; send us your VIN and we will tell you when the next one is ready and what it will cost, including delivery.
Will the N45B16 fit my BMW E90 316i?
Yes, the BMW E90 316i left the factory with the N45B16, so an N45B16 from another car is the direct replacement. The fifth 3 Series saloon was built 2005–2012, and the N45B16 was produced 2004–2011, so check that your car's build date falls inside that window. Confirm the drive type (rear-drive or xDrive), the gearbox (manual or automatic) and the emissions standard, because these can change the sump, the flywheel and the software. Send us the VIN and we check all of it for you.
How much is a replacement engine for a BMW E90 316i?
We do not have an N45B16 on the shelf for the E90 316i at the moment. Units arrive regularly; send us your VIN and we will tell you when the next one is ready and what it will cost, including delivery.
Will the N45B16 fit my BMW E87 116i?
Yes, the BMW E87 116i left the factory with the N45B16, so an N45B16 from another car is the direct replacement. The first 1 Series five-door was built 2004–2011, and the N45B16 was produced 2004–2011, so check that your car's build date falls inside that window. Confirm the drive type (rear-drive or xDrive), the gearbox (manual or automatic) and the emissions standard, because these can change the sump, the flywheel and the software. Send us the VIN and we check all of it for you.
How much is a replacement engine for a BMW E87 116i?
We do not have an N45B16 on the shelf for the E87 116i at the moment. Units arrive regularly; send us your VIN and we will tell you when the next one is ready and what it will cost, including delivery.
Will the N46B20 fit my BMW E90 318i?
The N46B20 is the original engine for the BMW E90 318i, which makes it the straightforward choice. The fifth 3 Series saloon was built 2005–2012, and the N46B20 was produced 2004–2012, so check that your car's build date falls inside that window. Confirm the drive type (rear-drive or xDrive), the gearbox (manual or automatic) and the emissions standard, because these can change the sump, the flywheel and the software. Send us the VIN and we check all of it for you.
How much is a replacement engine for a BMW E90 318i?
We do not have an N46B20 on the shelf for the E90 318i at the moment. Units arrive regularly; send us your VIN and we will tell you when the next one is ready and what it will cost, including delivery.
Will the N46B20 fit my BMW E87 118i?
Yes, the BMW E87 118i left the factory with the N46B20, so an N46B20 from another car is the direct replacement. The first 1 Series five-door was built 2004–2011, and the N46B20 was produced 2004–2012, so check that your car's build date falls inside that window. Confirm the drive type (rear-drive or xDrive), the gearbox (manual or automatic) and the emissions standard, because these can change the sump, the flywheel and the software. Send us the VIN and we check all of it for you.
How much is a replacement engine for a BMW E87 118i?
We do not have an N46B20 on the shelf for the E87 118i at the moment. Units arrive regularly; send us your VIN and we will tell you when the next one is ready and what it will cost, including delivery.
Will the N46B20 fit my BMW E84 X1 18i?
For the BMW E84 X1 18i, the N46B20 is the factory engine and the one to order. The first X1 was built 2009–2015, and the N46B20 was produced 2004–2012, so check that your car's build date falls inside that window. Confirm the drive type (rear-drive or xDrive), the gearbox (manual or automatic) and the emissions standard, because these can change the sump, the flywheel and the software. Send us the VIN and we check all of it for you.
How much is a replacement engine for a BMW E84 X1 18i?
We do not have an N46B20 on the shelf for the E84 X1 18i at the moment. Units arrive regularly; send us your VIN and we will tell you when the next one is ready and what it will cost, including delivery.
Will the N45B20S fit my BMW E90 320si?
The N45B20S is the original engine for the BMW E90 320si, which makes it the straightforward choice. The fifth 3 Series saloon was built 2005–2012, and the N45B20S was produced 2005–2007, so check that your car's build date falls inside that window. Confirm the drive type (rear-drive or xDrive), the gearbox (manual or automatic) and the emissions standard, because these can change the sump, the flywheel and the software. Send us the VIN and we check all of it for you.
How much is a replacement engine for a BMW E90 320si?
We do not have an N45B20S on the shelf for the E90 320si at the moment. Units arrive regularly; send us your VIN and we will tell you when the next one is ready and what it will cost, including delivery.
Will the N45B20S fit my BMW E87 120i?
For the BMW E87 120i, the N45B20S is the factory engine and the one to order. The first 1 Series five-door was built 2004–2011, and the N45B20S was produced 2005–2007, so check that your car's build date falls inside that window. Confirm the drive type (rear-drive or xDrive), the gearbox (manual or automatic) and the emissions standard, because these can change the sump, the flywheel and the software. Send us the VIN and we check all of it for you.
How much is a replacement engine for a BMW E87 120i?
We do not have an N45B20S on the shelf for the E87 120i at the moment. Units arrive regularly; send us your VIN and we will tell you when the next one is ready and what it will cost, including delivery.
N42 and N46 model-year guide
Use this year-by-year guide to see which N42 and N46 versions were in production when your car was built.
2001 — N42B18, N40B16 and N42B20 were in production. New this year: N42B18, N40B16 and N42B20.
2002 — N42B18, N40B16 and N42B20 were in production.
2003 — N42B18, N40B16 and N42B20 were in production.
2004 — N42B18, N40B16, N42B20, N46B18, N45B16 and N46B20 were in production. New this year: N46B18, N45B16 and N46B20. Last year for N42B18, N40B16 and N42B20.
2005 — N46B18, N45B16, N46B20 and N45B20S were in production. New this year: N45B20S.
2006 — N46B18, N45B16, N46B20 and N45B20S were in production.
2007 — N46B18, N45B16, N46B20 and N45B20S were in production. Last year for N46B18 and N45B20S.
2008 — N45B16 and N46B20 were in production.
2009 — N45B16 and N46B20 were in production.
2010 — N45B16 and N46B20 were in production.
2011 — N45B16 and N46B20 were in production. Last year for N45B16.
2012 — N46B20 was in production. Last year for N46B20.
Common N42 and N46 problems and what to check
No engine is perfect. These are the faults our workshop sees most often on the N42 and N46, what causes them and how to check a used unit before you buy.
Oil consumption
Valve stem seals and piston rings let oil through; consumption above one litre per 1,000 km is not unusual on neglected engines.
How to check: Ask for consumption figures and check the spark plugs for oil fouling.
Timing chain stretch
The N46 chain and tensioner wear, causing rattle and timing faults.
How to check: Listen for a rattle on a cold start and check the camshaft timing values.
Valvetronic motor and eccentric shaft sensor
Both can fail and leave the engine in limp mode.
How to check: Check for Valvetronic fault codes.
Vacuum pump and oil leaks
The vacuum pump seal and the valve cover gasket leak oil.
How to check: Look at the back of the head.
Crankcase ventilation
The CCV diaphragm splits, causing lean codes and a whistle.
How to check: Check for a whistle at idle.
Diagnosing a failing N42 and N46: symptoms and causes
If your current engine is showing one of these symptoms, this table helps you judge whether it can be repaired or whether a replacement N42 and N46 is the better route.
| Symptom | Likely cause |
|---|---|
| Knocking from the bottom of the engine | A deep knock that rises with engine speed usually means worn rod or main bearings. |
| Overheating or losing coolant | Coolant loss without visible leaks points to a head gasket or a cracked head; visible leaks point to the water pump, hoses, thermostat housing or expansion tank. |
| White smoke that smells sweet | Coolant burning in the cylinders, from a head gasket, a cracked head or, on diesels, a leaking EGR cooler. |
| Blue smoke | Oil burning in the cylinders. |
| Rough idle or misfire | Ignition coils, spark plugs, injectors and vacuum leaks are the usual causes. |
| Loss of power | Start with the simple things: air filter, boost leaks on turbo engines, fuel pressure and fault codes. |
| Rattle for a few seconds after a cold start | The classic sign of a weak timing chain tensioner or stretched chain. |
| Poor low-down torque and uneven idle | VANOS seals or solenoids. |
| Limp mode with a Valvetronic fault | The Valvetronic motor, its eccentric shaft sensor or the wiring. |
Knocking from the bottom of the engine. A deep knock that rises with engine speed usually means worn rod or main bearings. Stop driving: bearing failure ends with a broken connecting rod. A used engine is normally the most economical fix once the bottom end is damaged.
Overheating or losing coolant. Coolant loss without visible leaks points to a head gasket or a cracked head; visible leaks point to the water pump, hoses, thermostat housing or expansion tank. Overheating should be fixed before it warps the head.
White smoke that smells sweet. Coolant burning in the cylinders, from a head gasket, a cracked head or, on diesels, a leaking EGR cooler. Check the coolant level and look for oil in the coolant.
Blue smoke. Oil burning in the cylinders. A puff on start-up points to valve stem seals; constant smoke under load points to piston rings or, on turbo engines, turbo seals.
Rough idle or misfire. Ignition coils, spark plugs, injectors and vacuum leaks are the usual causes. A misfire on one cylinder that moves when you swap coils is a coil; one that stays is a plug, injector or compression problem.
Loss of power. Start with the simple things: air filter, boost leaks on turbo engines, fuel pressure and fault codes. A gradual loss with poor compression on a test points to internal wear.
Rattle for a few seconds after a cold start. The classic sign of a weak timing chain tensioner or stretched chain. It must be checked quickly: a chain that jumps a tooth can bend valves.
Poor low-down torque and uneven idle. VANOS seals or solenoids. The engine may run well at high revs but feel flat and lumpy at low speed.
Limp mode with a Valvetronic fault. The Valvetronic motor, its eccentric shaft sensor or the wiring. The engine runs on a reduced throttle until it is repaired.
Repair or replace your N42 and N46?
As a rule, bolt-on faults are worth repairing and internal damage is not. Seals, sensors, coils, injectors, pumps and turbos can be replaced in the car. Once the bearings, crankshaft, bores or head of an N42 and N46 are damaged, a used engine is usually cheaper and quicker than a rebuild.
Ask your workshop for a written diagnosis before deciding. A compression test, an oil analysis and a borescope inspection take an hour or two and remove most of the guesswork.
N42 and N46 maintenance and running costs
| Item | Recommendation |
|---|---|
| Engine oil | 5W-30 BMW Longlife-01 or Longlife-04, about 4.25 litres. |
| Timing drive | Timing chain at the front with balance shafts. |
| Service interval | Oil every 15,000 km; shorten to 10,000 km to protect the chain. |
Replace the timing chain, tensioner and valve stem seals when fitting a high-mileage used N46.
The single best thing you can do for an N42 and N46 is to change the oil more often than the longest factory interval. Clean oil protects bearings, chains, VANOS units and turbochargers, and costs far less than any of them.
Buying a used N42 and N46: the full checklist
Work through these points before you order a used N42 and N46, whoever you buy from.
- Confirm the exact engine code. Read the code stamped on the block and compare it with the code for your car. Send us the last seven characters of the VIN and we confirm the match before anything is paid.
- Ask how the donor car was damaged. Most good used engines come from cars with body damage. A front-end impact can crack sensors, the timing cover or the sump; a rear or side impact usually leaves the engine untouched. The yard records the damage on each unit.
- Compression or leak-down figures. Even compression across all cylinders tells you more than mileage. Ask for the figures, not just a pass or fail, and compare the highest and lowest readings: a spread above 10 to 15 percent deserves a question.
- Look at the oil and coolant. Clean oil without metal particles and coolant without oil are good signs. Milky oil, oily coolant or a burnt smell mean the engine needs further checks before it is fitted.
- Photographs from every side. Good suppliers photograph the actual engine you will receive. Look for the block stamp, the sump, the timing cover and any broken brackets or connectors in the pictures.
- List of what is fitted. Engines are sold with different ancillaries: some have the turbo, injectors, manifolds, alternator and starter, others are long blocks. Agree the list in writing so you know which parts must come from your old engine.
- Sump, oil pickup and drive variants. Rear-drive, xDrive and front-drive cars can use different sumps, oil pickups and engine mounts even with the same engine code. Check that the sump matches your subframe and front axle.
- Gearbox and flywheel match. Manual and automatic engines differ at the flywheel or flexplate, and sometimes at the crankshaft spigot. Make sure the engine you buy matches your gearbox or that you transfer the right parts.
- Warranty terms in writing. Read what the warranty covers, how long it runs and what fitting conditions apply. Most warranties require a qualified workshop, new fluids and filters, and replacement of the cooling parts that caused the original failure.
- Why your old engine failed. Before fitting a replacement, find out why the original failed. An overheating radiator, a blocked intercooler or a failed turbo can destroy a second engine if they are not fixed.
- Timing chain noise. Listen for a rattle at the front of the engine for the first seconds after a cold start. On an engine that cannot be run, look at the chain guides through the oil filler or with the valve cover off.
- VANOS operation. Rough idle, a rattle from the front of the head and a loss of torque at low revs point to VANOS seals or solenoids. These are serviceable parts and are easier to renew with the engine out.
- Double VANOS units and solenoids. Ask for the adaptation values or fault history if the engine was running. Solenoids are inexpensive and are often replaced as a matter of course on a used engine.
- Valvetronic motor and eccentric shaft sensor. The Valvetronic motor and its sensor cause limp-mode faults when they fail. Inspect the connector and the seal around the motor for oil.
N42 and N46 prices: what you should pay
We do not have an N42 and N46 on the shelf at the moment. Send us your VIN or the code you need and the desk will tell you when the next unit arrives and what it will cost.
N42 and N46 engines in stock now
Fitting a replacement N42 and N46
These are the steps we recommend to every workshop fitting one of our N42 and N46 engines.
- Compare the engines side by side. Put the replacement next to the old engine and compare sensors, brackets, connectors, the sump, the starter and the flywheel or flexplate. Note anything that must be transferred.
- Transfer the parts that differ. Move the parts that are specific to your car, such as the engine harness on some models, the sump on xDrive cars or the air conditioning compressor bracket. Use new seals and gaskets for everything you move.
- Replace the rear main seal and drive parts. With the engine out, the rear crankshaft seal is easy to reach. Fit a new one, inspect the flywheel and clutch on manual cars or the converter seal on automatics.
- Renew the cooling system. Most engine failures start with cooling. Fit a new water pump, thermostat and hoses, check the radiator and fan, and use the correct coolant.
- Fit new engine mounts. Old mounts transfer vibration and can let the engine move enough to damage hoses. They are cheap and easy to replace with the engine out.
- Inspect or replace the timing chain parts. Look at the guides and tensioner. On high-mileage engines, replacing them now costs far less than doing it later.
- Clean the intake. If the old engine failed internally, debris can be in the intake or intercooler. Clean them so nothing reaches the new engine.
- Fill with the right oil and prime it. Fill with new oil of the correct specification and a new filter. Crank with the fuel and ignition disabled until oil pressure builds.
- Coding and adaptations. On modern BMWs, the engine ECU must be matched to the car's immobiliser (CAS, FEM or BDC). Reset adaptations, register the battery and clear faults with diagnostic software.
- Reset VANOS adaptations. Clear the VANOS adaptations so the ECU learns the camshaft positions of the new engine.
- Teach the Valvetronic limit stops. Run the Valvetronic learning routine so the ECU knows the eccentric shaft limits.
- First start and leak check. Start the engine, let it idle and watch oil pressure, temperature and fault codes. Check for leaks and bleed the cooling system.
- First 1,000 km. Drive gently for the first few hundred kilometres, vary the engine speed and avoid full load. Change the oil and filter after about 1,000 km to remove any assembly debris.
Tuning and upgrades
Tuning potential is limited. Most owners looking for more power choose a six-cylinder swap.
Whatever you plan, start with a healthy engine: a compression test, fresh fluids and the known weak parts replaced. Power upgrades amplify any existing problem.
N42 and N46 compared with similar BMW engines
Buyers often compare the N42 and N46 with these engines. Here is how they line up.
| Engine | Power | Years | Median price in stock |
|---|---|---|---|
| N42 and N46 | 115–173 hp | 2001–2012 | on request |
| M42 and M44 | 140–140 hp | 1989–2000 | 6.459,00 € |
| N43 | 122–170 hp | 2007–2011 | 848,00 € |
| N20 and N26 | 170–245 hp | 2011–2017 | 2.612,00 € |
The M42 and M44 is milder (up to 140 hp against 173 hp) and uses timing chain at the front with guides and a hydraulic tensioner. Its best-known faults are head gasket and timing chain guides and tensioner. Read the M42 and M44 guide.
The N43 is milder (up to 170 hp against 173 hp) and uses timing chain at the front. Its best-known faults are piezo injectors and ignition coils and spark plugs. Read the N43 guide.
The N20 and N26 reaches higher outputs (up to 245 hp against 173 hp) and uses timing chain at the rear (gearbox end). Its best-known faults are timing chain guide and oil pump drive chain. Read the N20 and N26 guide.
Delivery, warranty and payment
Before an N42 and N46 engine leaves our Hamburg yard it is drained of oil and coolant, every opening is sealed, and it is strapped to a pallet and wrapped. We send photographs of the packed unit and the tracking details.
Delivery is door to door and included in the price. Most European addresses receive the engine within five to ten working days; Germany and its neighbours are usually faster.
A 12-month warranty covers eligible internal failure when the engine is fitted by a qualified workshop with new fluids and filters. You can pay by card, bank transfer or crypto and receive the invoice by email straight away.
We deliver N42 and N46 engines from Hamburg to customers across Europe and beyond. Typical door-to-door times and customs status:
| Country | Typical delivery | Customs and VAT |
|---|---|---|
| Germany | 2–4 working days | No customs; German VAT on the invoice |
| Netherlands | 3–5 working days | EU delivery, no customs |
| Belgium | 3–5 working days | EU delivery, no customs |
| Austria | 3–5 working days | EU delivery, no customs |
| Denmark | 3–5 working days | EU delivery, no customs |
| Poland | 3–6 working days | EU delivery, no customs |
| Czech Republic | 3–6 working days | EU delivery, no customs |
| France | 4–7 working days | EU delivery, no customs |
| Italy | 5–8 working days | EU delivery, no customs |
| Spain | 5–8 working days | EU delivery, no customs |
| Portugal | 6–9 working days | EU delivery, no customs |
| Sweden | 5–8 working days | EU delivery, no customs |
| Norway | 6–10 working days | Export; import VAT and duty in Norway |
| Switzerland | 5–8 working days | Export; import VAT and duty in Switzerland |
| United Kingdom | 5–10 working days | Export; UK import VAT and duty on arrival |
| Ireland | 6–10 working days | EU delivery, no customs |
| United States | Quoted per order | Export; US import duties apply |
| United Arab Emirates | Quoted per order | Export; UAE import duties apply |
Times are typical for pallet delivery after dispatch and can vary with holidays and remote addresses. Business buyers in the EU with a valid VAT number can order without German VAT.
Questions buyers ask about the N42 and N46
Will the N46B20 engine fit my BMW E46 318i?
Yes, if your BMW E46 318i was built with the N46B20. BMW used this 2.0 liter (1,995 cc) petrol engine with 110 kW (150 HP) in the E46 318i from about 2004 to 2012.
Some E46 318i cars were built with a different engine: the M43B18. These look alike from the outside, so check the code on your engine or send us your VIN.
Also tell us if your E46 has a manual or an automatic gearbox. The flywheel or the flex plate and some sensors depend on it.
Not sure? Send us your VIN and your gearbox code. We match the engine family, the year window and the parts on the engine before anything is reserved, and the check is free.
See all N46 Engines · Search N46B20 in the shop
How much is a replacement N46B20 engine for a BMW E46 318i?
A used N46B20 for the BMW E46 318i costs from about 1.000 € to 1.700 € in our yard. The price depends on the year, the mileage and the parts that come with the engine.
Shipping is a flat 249 € per order. It is added once at checkout and printed on the invoice, so there is no extra fee later. Inside the EU there is no import duty. Outside the EU, the receiver pays local duty and VAT.
A replacement engine is often much cheaper than rebuilding a damaged one, and much faster. The N46B20 you buy is photographed and checked in Hamburg before it is listed.
Eligible engines come with a 12 months warranty from the delivery date. It covers internal mechanical failure under normal use and correct fitting by a qualified mechanic or workshop. Not sure? Send us your VIN and your gearbox code. We match the engine family, the year window and the parts on the engine before anything is reserved, and the check is free.
See all N46 Engines · Search N46B20 in the shop
Will the N46B20 engine fit my BMW E90 320i?
Yes, if your BMW E90 320i was built with the N46B20. BMW used this 2.0 liter (1,995 cc) petrol engine with 110 kW (150 HP) in the E90 320i from about 2004 to 2012.
In our records the N46B20 is the engine for the E90 320i, which makes the match simple. Still, check the code on your old engine or send us your VIN.
Also tell us if your E90 has a manual or an automatic gearbox. The flywheel or the flex plate and some sensors depend on it.
Not sure? Send us your VIN and your gearbox code. We match the engine family, the year window and the parts on the engine before anything is reserved, and the check is free.
See all N46 Engines · Search N46B20 in the shop
How much is a replacement N46B20 engine for a BMW E90 320i?
A used N46B20 for the BMW E90 320i costs from about 1.000 € to 1.700 € in our yard. The price depends on the year, the mileage and the parts that come with the engine.
Shipping is a flat 249 € per order. It is added once at checkout and printed on the invoice, so there is no extra fee later. Inside the EU there is no import duty. Outside the EU, the receiver pays local duty and VAT.
A replacement engine is often much cheaper than rebuilding a damaged one, and much faster. The N46B20 you buy is photographed and checked in Hamburg before it is listed.
Eligible engines come with a 12 months warranty from the delivery date. It covers internal mechanical failure under normal use and correct fitting by a qualified mechanic or workshop. Not sure? Send us your VIN and your gearbox code. We match the engine family, the year window and the parts on the engine before anything is reserved, and the check is free.
See all N46 Engines · Search N46B20 in the shop
Will the N46B20 engine fit my BMW E87 120i?
Yes, if your BMW E87 120i was built with the N46B20. BMW used this 2.0 liter (1,995 cc) petrol engine with 110 kW (150 HP) in the E87 120i from about 2004 to 2012.
In our records the N46B20 is the engine for the E87 120i, which makes the match simple. Still, check the code on your old engine or send us your VIN.
Also tell us if your E87 has a manual or an automatic gearbox. The flywheel or the flex plate and some sensors depend on it.
Not sure? Send us your VIN and your gearbox code. We match the engine family, the year window and the parts on the engine before anything is reserved, and the check is free.
See all N46 Engines · Search N46B20 in the shop
How much is a replacement N46B20 engine for a BMW E87 120i?
A used N46B20 for the BMW E87 120i costs from about 1.000 € to 1.700 € in our yard. The price depends on the year, the mileage and the parts that come with the engine.
Shipping is a flat 249 € per order. It is added once at checkout and printed on the invoice, so there is no extra fee later. Inside the EU there is no import duty. Outside the EU, the receiver pays local duty and VAT.
A replacement engine is often much cheaper than rebuilding a damaged one, and much faster. The N46B20 you buy is photographed and checked in Hamburg before it is listed.
Eligible engines come with a 12 months warranty from the delivery date. It covers internal mechanical failure under normal use and correct fitting by a qualified mechanic or workshop. Not sure? Send us your VIN and your gearbox code. We match the engine family, the year window and the parts on the engine before anything is reserved, and the check is free.
See all N46 Engines · Search N46B20 in the shop
Will the N46B20 engine fit my BMW E60 520i?
Yes, if your BMW E60 520i was built with the N46B20. BMW used this 2.0 liter (1,995 cc) petrol engine with 110 kW (150 HP) in the E60 520i from about 2004 to 2012.
In our records the N46B20 is the engine for the E60 520i, which makes the match simple. Still, check the code on your old engine or send us your VIN.
Also tell us if your E60 has a manual or an automatic gearbox. The flywheel or the flex plate and some sensors depend on it.
Not sure? Send us your VIN and your gearbox code. We match the engine family, the year window and the parts on the engine before anything is reserved, and the check is free.
See all N46 Engines · Search N46B20 in the shop
How much is a replacement N46B20 engine for a BMW E60 520i?
A used N46B20 for the BMW E60 520i costs from about 1.000 € to 1.700 € in our yard. The price depends on the year, the mileage and the parts that come with the engine.
Shipping is a flat 249 € per order. It is added once at checkout and printed on the invoice, so there is no extra fee later. Inside the EU there is no import duty. Outside the EU, the receiver pays local duty and VAT.
A replacement engine is often much cheaper than rebuilding a damaged one, and much faster. The N46B20 you buy is photographed and checked in Hamburg before it is listed.
Eligible engines come with a 12 months warranty from the delivery date. It covers internal mechanical failure under normal use and correct fitting by a qualified mechanic or workshop. Not sure? Send us your VIN and your gearbox code. We match the engine family, the year window and the parts on the engine before anything is reserved, and the check is free.
See all N46 Engines · Search N46B20 in the shop
What is the BMW N46B20 engine?
The BMW N46B20 is a 2.0 liter (1,995 cc) petrol engine from the N46 family. It has an inline 4, DOHC, 16 valve layout with no turbo (naturally aspirated), and makes 110 kW (150 HP) with 200 Nm of torque. BMW built it from 2004 to 2012 and it meets the Euro 4 emission standard.
You find the N46B20 in the BMW E90 320i, BMW E87 120i, BMW E60 520i and BMW E46 318i. What we list: BMW N46 1.6 and 2.0 petrol engines for 316i and 320i.
At Autowerke Engines every N46B20 is a real used engine from our yard in Hamburg. Before a unit is listed, the yard checks the engine code against the listing, writes down the parts fitted to it, seals every opening and photographs the real engine you will receive. Each listing shows the year, the mileage and the price, so you can compare units side by side.
Not sure? Send us your VIN and your gearbox code. We match the engine family, the year window and the parts on the engine before anything is reserved, and the check is free.
See all N46 Engines · Search N46B20 in the shop
How much does a used BMW N46B20 engine cost?
A used BMW N46B20 engine in our yard usually costs between 1.000 € and 1.700 €. The exact price depends on the year, the mileage and the parts that come with the engine.
Our units show recorded mileage from about 22,000 km up to around 200,000 km. Lower mileage and more ancillaries mean a higher price. Each listing shows its own price, and the price you see is the price you pay. Prices include VAT for private buyers.
Shipping is a flat 249 € per order. It is added once at checkout and printed on the invoice, so there is no extra fee later. If you order a gearbox or a second engine on the same order, the fee is still charged once.
Inside the EU there is no import duty. For the UK and other non-EU countries, import duty and local VAT are paid by the receiver, and we supply a commercial invoice.
See all N46 Engines · Search N46B20 in the shop
Which cars use the BMW N46B20 engine?
BMW fitted the N46B20 to the BMW E90 320i, BMW E87 120i, BMW E60 520i and BMW E46 318i. These cars were built with this engine from about 2004 to 2012.
The badge on the boot is not enough to be sure. The same model name can hide two different engines, for example after a facelift or a change in emission rules. Always read the engine code stamped on the block, or look it up with your VIN.
The N46B20 is the only N46 version we list, which makes it easy to pick, but the wiring and the engine computer still need to match your car.
Not sure? Send us your VIN and your gearbox code. We match the engine family, the year window and the parts on the engine before anything is reserved, and the check is free.
See all N46 Engines · Search N46B20 in the shop
How much power and torque does the BMW N46B20 have?
From the factory the BMW N46B20 makes 110 kW (150 HP) and 200 Nm of torque. It is a 2.0 liter (1,995 cc) inline 4, DOHC, 16 valve petrol engine with no turbo (naturally aspirated).
Without a turbo, the power builds smoothly with the revs. A clean air intake, healthy ignition and the correct fuel are key to getting the full figure.
A used engine reaches its factory numbers when it is fitted with the matching engine computer and software, and serviced with the right oil and filters. If the engine computer from your car is a different version, a specialist may need to code it.
Every N46B20 on our site lists its year and mileage. If you want more photos or a short video of a unit, ask the desk and we send them before you pay.
See all N46 Engines · Search N46B20 in the shop
How do I know a used N46B20 engine is in good shape?
Each engine in the yard is inspected in Hamburg. The code is matched to the listing, the parts on the engine are recorded, the openings are sealed and the real unit is photographed. An inspection certificate for the unit can travel with the order when you ask for it.
When you look at a listing, check the recorded mileage, the year and the photos of the ports and the stamp. Ask for photos of anything you want to see closer. If you want more photos or a short video of a unit, ask the desk and we send them before you pay.
On a petrol engine like the N46B20, a careful fitter will also look at the spark plugs, the coils and the timing side before the engine goes in.
If the engine fails inside under normal use, the warranty covers you. Eligible engines come with a 12 months warranty from the delivery date. It covers internal mechanical failure under normal use and correct fitting by a qualified mechanic or workshop.
See all N46 Engines · Search N46B20 in the shop
What comes with a used N46B20 engine?
Each N46B20 is sold as described on its own listing. The yard writes down the parts that are fitted to that unit, such as the turbo, the injectors, the manifolds or the alternator, so you know what arrives.
Some units are long engines with few ancillaries, others are more complete. If you need a part that is not listed, ask the desk. We often have the matching items in the yard.
Every engine is drained, sealed at each opening, strapped to a heat-treated pallet and shrink-wrapped, then photographed before it leaves the yard.
On delivery, the carrier brings the pallet to the kerb or a loading bay. Please have a forklift, a pallet truck or an engine crane ready.
See all N46 Engines · Search N46B20 in the shop
Is the BMW N46B20 a diesel or petrol engine?
The N46B20 is a petrol engine. It is a 2.0 liter (1,995 cc) inline 4, DOHC, 16 valve unit with no turbo (naturally aspirated), and it was built to the Euro 4 emission standard.
The emission standard matters for registration and for low-emission zones in many cities. When you replace an engine with the same code, the car keeps the same paperwork and the same emission class.
Petrol versions need the correct catalytic converters and oxygen sensors on the car to stay legal and to keep the engine computer happy. Reuse the parts from your car if they are in good condition.
If you are not sure which version you need, send us your VIN. We tell you the right code for free.
See all N46 Engines · Search N46B20 in the shop
Are there other versions of the BMW N46B20?
In our yard the N46B20 is the only listed version of the N46 family. It makes 110 kW (150 HP) and 200 Nm, and was built from 2004 to 2012.
Engines in one family share a basic block, but the turbo, the injection, the sensors and the engine computer can differ. A higher power version often has different pistons, a bigger turbo or a different fuel system.
This is why we ask for the exact code. Fitting a different version can work, but the wiring, the software and sometimes the gearbox must be changed to match.
Not sure? Send us your VIN and your gearbox code. We match the engine family, the year window and the parts on the engine before anything is reserved, and the check is free.
See all N46 Engines · Search N46B20 in the shop
How long does delivery of an N46B20 engine take?
Orders confirmed before 14:00 CET on a working day leave Hamburg the same day. Later and weekend orders leave the next working day. Delivery to the Netherlands, Belgium, Germany, France, Luxembourg and Denmark takes 1 to 3 working days.
Spain, Italy, Portugal, Poland, Czechia, Austria, Ireland, the Nordics and the Baltics take 2 to 5 working days. Greek and Spanish islands, Malta, Cyprus and remote areas take 4 to 8 working days. The UK and other countries outside the EU are quoted one by one.
Shipping is a flat 249 € per order. It is added once at checkout and printed on the invoice, so there is no extra fee later. Every engine is drained, sealed at each opening, strapped to a heat-treated pallet and shrink-wrapped, then photographed before it leaves the yard.
You get a tracking number when the pallet is collected. Check the wrapping before you sign, and note any damage on the paperwork.
See all N46 Engines · Search N46B20 in the shop
What should I replace when I fit a used N46B20 engine?
A used engine lasts longest when it starts life in your car with fresh fluids and new seals. Fit a new oil filter and fresh oil of the grade BMW lists for this engine, and refill the coolant with the correct BMW antifreeze mix. Change the drive belt, the thermostat and the water pump seals if they look tired, because they are cheap while the engine is out. Use new gaskets for the exhaust manifold, the intake and the sump plug, and check every hose clip before the first start.
Look at the engine mounts and the clutch or the torque converter while the engine is out. Old mounts can crack a new engine's brackets, and a worn clutch is much easier to change now.
Before the first start, turn the engine over without fuel until the oil pressure light goes out. Then let it idle, check for leaks, and drive gently for the first few hundred kilometres.
The warranty asks for fitting by a qualified mechanic and the correct oil, coolant and filters. Keep your receipts in case you ever need to make a claim.
See all N46 Engines · Search N46B20 in the shop
Does a used N46B20 engine come with a warranty?
Yes. Eligible engines come with a 12 months warranty from the delivery date. It covers internal mechanical failure under normal use and correct fitting by a qualified mechanic or workshop.
The warranty does not cover damage from wrong fitting, overheating, low oil, wrong fluids or fuel, engines that were opened or modified without our approval, or labour and towing costs.
To claim, send us your order number, a short description of the problem, photos or a video, and a mechanic's report if we ask for one. If the claim is approved, we repair, replace or refund the engine.
Keep the receipts for the fitting, the oil and the filters. They make any claim quick and simple.
See all N46 Engines · Search N46B20 in the shop
Can you check if an N46B20 fits my car with my VIN?
Yes, and it is free. Send the 17-character VIN of your car and, if you have it, the gearbox code. We check the engine family, the build year window and the parts your car needs.
For the N46B20, we confirm that your car was built with this code or with a version that can take it. BMW used it in the BMW E90 320i, BMW E87 120i, BMW E60 520i and BMW E46 318i.
We only reserve an engine once the match is confirmed, so you never pay for the wrong unit. You can reach the Hamburg desk by email at autowerkeengines@gmail.com, or by phone and WhatsApp on +49 15510 030835, Monday to Friday, 9:00 to 16:00 CET.
You can also use the VIN check on our site. It reads the year, the make, the model and the engine from the public vehicle register.
See all N46 Engines · Search N46B20 in the shop
What should I know about the BMW N46 engine?
BMW N46 1.6 and 2.0 petrol engines for 316i and 320i. We list one version: N46B20 (2.0 liter (1,995 cc), 110 kW (150 HP), 2004 to 2012).
Because there is only one version, the code is easy to match. You still need the engine computer and wiring that suit your car.
The N46 family was used in chassis E90, E87, E60 and E46. The photos on each listing show the actual engine, not a stock picture. The yard checks the code, records what is bolted on, and seals the openings before the engine is offered.
Not sure? Send us your VIN and your gearbox code. We match the engine family, the year window and the parts on the engine before anything is reserved, and the check is free.
What should I check on a used BMW N46 engine?
Start with the basics: the engine code on the block, the recorded mileage and the photos. Make sure the code matches your car and the parts you need are on the unit.
On an N46 petrol engine, a fitter usually checks the spark plugs, the coils, the timing side and the oil seals. These parts are easy to check before fitting and easy to change if needed.
You can ask for extra photos, a close-up of the code stamp or a short video before you order. An inspection certificate can travel with the order on request.
Once fitted, change the oil and filter early and drive gently at first. Report any problem right away so the warranty stays valid.
See all N46 Engines · Inspection certificate
Which years were BMW N46 engines made?
BMW built the N46 engines we list from about 2004 to 2012. The N46B20 ran from 2004 to 2012.
They went into chassis E90, E87, E60 and E46. The exact year of a car matters, because BMW sometimes changed the engine version or its parts in the middle of a model's life.
Each listing in our yard names the engine year, so you can match it to the build date of your car.
Not sure? Send us your VIN and your gearbox code. We match the engine family, the year window and the parts on the engine before anything is reserved, and the check is free.
Glossary
- VANOS — BMW's variable camshaft timing system. It adjusts the intake camshaft (single VANOS) or both camshafts (double VANOS) to improve torque and emissions.
- Valvetronic — BMW's variable valve lift system. It controls engine load with the intake valves instead of a throttle plate, improving economy.
- Long block — An engine with the block, head and internals but without most ancillaries such as manifolds, turbo, alternator or starter.
- Dressed engine — An engine with most ancillaries fitted, ready to install with fewer parts transferred.
- Compression test — A measurement of the pressure each cylinder builds when cranked. Even readings show healthy rings and valves.
- Leak-down test — A test that pressurises each cylinder and measures how much air escapes, showing where any leak is.
- LCI — Life Cycle Impulse, BMW's name for a mid-life update. Engines often change at the LCI.
- xDrive — BMW's all-wheel-drive system. xDrive cars often use a different sump and oil pickup.
- DME — Digital Motor Electronics, BMW's name for the engine control unit.
- CAS, FEM and BDC — The immobiliser and body modules that must be matched to the engine control unit on modern BMWs.
- Timing chain tensioner — A hydraulic or spring device that keeps the timing chain tight. Worn tensioners cause cold-start rattle.
- TU — Technical Update, BMW's suffix for a revised version of an engine.
Our verdict
The N42 and N46 has a clear set of strengths and a known list of weak points. Check the code against your VIN, ask for compression figures and photographs, replace the known weak parts while the engine is out, and fit it with fresh fluids and filters. Do that and a used N42 and N46 will give years of service.
Ready to order, or need help choosing? Browse every N42 and N46 in stock, contact the Hamburg desk or send us your VIN on WhatsApp.
