BMW X3 30i (G01) engine: which one, problems and replacement

The BMW X3 30i in the third X3 generation (G01, built 2017–2024) was built with 3 different engines over its life: the B46B20 (258 hp, 2015–2026), the B48B20TU (258 hp, 2018–2026) and the B48B20B (258 hp, 2019–2026).

Below you will find how to identify the engine in your X3 30i, the faults to look for, current prices for a replacement and the swap options that make sense.

• Generation: third X3, 2017–2024
• Body styles: G01 (SAV)
• Engines: B46B20, B48B20TU, B48B20B
• Output: 258 hp
• Replacement engines in stock: 35 from 1.143,00 €

Which engine is in your X3 30i?

B46B20 in the X3 30i

The B46B20 was used in the G01 X3 30i, built 2015–2026. It is a 2.0 L turbocharged petrol inline-4 with 258 hp and 400 Nm. It has the same output as the B48B20TU and B48B20B, so the build date decides which one your car has.

Reading the code: B marks a B-series code, BMW's modular engine family introduced from 2013 with 500 cc per cylinder; 46 is the family number; B stands for petrol, longitudinal installation for rear-drive and xDrive cars; 20 is the capacity in decilitres, so 2.0 litres.

B48B20TU in the X3 30i

The B48B20TU was used in the G01 X3 30i, built 2018–2026. It is a 2.0 L turbocharged petrol inline-4 with 258 hp and 400 Nm. It has the same output as the B46B20 and B48B20B, so the build date decides which one your car has.

Reading the code: B marks a B-series code, BMW's modular engine family introduced from 2013 with 500 cc per cylinder; 48 is the family number; B stands for petrol, longitudinal installation for rear-drive and xDrive cars; 20 is the capacity in decilitres, so 2.0 litres; TU identifies the technical update.

B48B20B in the X3 30i

The B48B20B was used in the G01 X3 30i, built 2019–2026. It is a 2.0 L turbocharged petrol inline-4 with 258 hp and 400 Nm. It has the same output as the B46B20 and B48B20TU, so the build date decides which one your car has.

Reading the code: B marks a B-series code, BMW's modular engine family introduced from 2013 with 500 cc per cylinder; 48 is the family number; B stands for petrol, longitudinal installation for rear-drive and xDrive cars; 20 is the capacity in decilitres, so 2.0 litres; B identifies the version or output stage.

X3 30i engines by model year

The engine changed 2 times during the G01 run, in 2018 and 2019. Changes usually come with BMW's mid-life update (LCI) or a new emissions standard, so a car registered early in a year can still have the older engine. The VIN settles it.

Other cars with the same engine as the X3 30i

A replacement engine does not have to come from another X3 30i. These models left the factory with the same engine code, so a unit from any of them is a candidate donor once the sump, mounts and ancillaries are matched to your car.

B46B20: BMW F30 330i SULEV, BMW G30 530i SULEV.

B48B20TU: BMW G20 330i, BMW G30 530i, BMW G22 430i.

B48B20B: BMW G20 330i, BMW G30 530i.

How to confirm your engine code

Because the X3 30i used more than one engine, the badge alone does not tell you which one your car has. The build date is the first clue; the VIN is the proof. Send us the last seven characters of the VIN and we read the engine code from BMW's records, or look for the code stamped on the block. How to find your BMW engine code.

Known X3 30i engine problems

B46B20, B48B20TU and B48B20B (B48 and B46 family)

The B46B20, B48B20TU and B48B20B in the X3 30i share the known weak points of the B48 and B46 family. Full B48 and B46 guide.

Coolant leaks. Thermostat housings and coolant pipes leak.

Oil filter housing gasket. Leaks at higher mileage.

PCV and valve cover. Valve cover seals and PCV parts fail.

Water pump. The water pump can leak.

B46B20, B48B20TU and B48B20B (B48 and B46 family)

The B46B20, B48B20TU and B48B20B in the X3 30i share the known weak points of the B48 and B46 family. Full B48 and B46 guide.

Coolant leaks. Thermostat housings and coolant pipes leak.

Oil filter housing gasket. Leaks at higher mileage.

PCV and valve cover. Valve cover seals and PCV parts fail.

Water pump. The water pump can leak.

Symptoms to watch for on the X3 30i

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.

Rattle or whine from the gearbox end. On engines with the timing chain at the rear, a rattle or whine from the back of the engine is the warning sign of chain stretch or guide wear.

Whistle, loss of boost or limp mode. A split charge pipe, a sticking wastegate or worn turbo bearings. Check the pipes first, then the turbo shaft for play.

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.

Long cranking before the engine starts. On direct-injection engines, a weak high-pressure fuel pump or leaking injector lets pressure drop when the engine is off.

Looking after the X3 30i engine

B48 and B46 engines

• Oil: 0W-20 or 0W-30 BMW Longlife-17 FE+ or 01, about 5.25 litres.
• Service interval: Oil every 15,000 km or yearly.
• Timing drive: Timing chain at the rear (gearbox end).
• Workshop notes: Check front-drive (B48A) or rear-drive (B48B) before ordering.

B48 and B46 engines

• Oil: 0W-20 or 0W-30 BMW Longlife-17 FE+ or 01, about 5.25 litres.
• Service interval: Oil every 15,000 km or yearly.
• Timing drive: Timing chain at the rear (gearbox end).
• Workshop notes: Check front-drive (B48A) or rear-drive (B48B) before ordering.

Buying a used engine for the X3 30i: checklist

1. 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.
2. 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.
3. 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.
4. 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.
5. 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.
6. Turbocharger shaft play and oil. Rotate the compressor wheel by hand. A small amount of side play is normal; in-and-out play or wheel contact with the housing is not. Oil pooled in the intake or intercooler pipes points to worn seals.
7. 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.
8. Gearbox-end timing chain. On this engine the timing chain sits at the gearbox end, so replacing it normally means removing the engine. If the chain has not been replaced, the time to do it is before the engine goes into your car.
9. 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.
10. 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.
11. 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.
12. Injectors and high-pressure fuel pump. Direct-injection engines rely on high-pressure pumps and precise injectors. Ask whether the injectors are original or updated and whether there were fuel pressure faults.

BMW X3 30i replacement engine cost

Across 35 X3 30i engine units in our stock today, prices start at 1.143,00 € and reach 4.795,00 €. The median — the price in the middle of the range — is 2.294,00 €.

Prices depend on the exact version, the donor's mileage, how complete the engine is and the demand for that code. Higher-output versions, low mileage and dressed engines with turbo, injectors and ancillaries cost more; long blocks and higher mileage cost less.

X3 30i engine prices by model year

Engines from 2000–2004 have a median of 1.143,00 €, while units from 2020–2024 sit at 2.576,00 €. Newer engines usually cost more because they come from younger donor cars with lower mileage and later updates.

X3 30i engine prices by mileage

Mileage matters less than history on a well-maintained BMW engine, but it is a useful guide. A low-mileage unit from a younger car gives you more life for a modest premium.

6 of these come from G01 donor cars, priced from 1.310,00 € to 3.241,00 €. An engine from the same body is the most direct swap because the sump, mounts and ancillaries already match.

On top of the engine, budget for the workshop's labour and the parts that are best replaced while the engine is out: engine mounts, the rear main seal, cooling parts, a clutch or converter seal, fluids and filters.

Replacement engines in stock for the X3 30i

Here is a selection of X3 30i engines currently on our shelves, photographed in the yard. Click any of them for the full photographs, mileage and specification.

BMW X3 30i G01 B48B20B Engine 2018 · 165,000 km1.310,00 €BMW X3 30i G01 B48B20B Engine 2020 · 146,000 km2.648,00 €BMW G01 X3 30i B48B20B Complete Engine2.294,00 €B48B20B Complete Engine BMW X3 30i G01 · 234,000 km2.202,00 €BMW B48B20B Engine X3 30i G01 20201.599,00 €

BMW X3 30i G01 B48B20B Engine 2018 · 165,000 km — 1.310,00 €, reduced from 1.650,00 €. It comes from a 2018 donor car with 165,000 km, and 8 units are available. We can confirm fitment against your VIN the same day.

BMW X3 30i G01 B48B20B Engine 2020 · 146,000 km — 2.648,00 €, reduced from 3.600,00 €. It comes from a 2020 donor car with 146,000 km, and 30 units are available. We can confirm fitment against your VIN the same day.

BMW G01 X3 30i B48B20B Complete Engine — 2.294,00 €, reduced from 2.800,00 €. It comes from a recorded donor car, and 27 units are available. The listing shows every side of the engine and the fitted parts.

B48B20B Complete Engine BMW X3 30i G01 · 234,000 km — 2.202,00 €, reduced from 2.500,00 €. It comes from a recorded donor car with 234,000 km, and 18 units are available. We can confirm fitment against your VIN the same day.

BMW B48B20B Engine X3 30i G01 2020 — 1.599,00 €, reduced from 1.900,00 €. It comes from a 2020 donor car, and 12 units are available. We can confirm fitment against your VIN the same day.

Will it fit my X3 30i?

Will the B46B20 fit my BMW G01 X3 30i?

The B46B20 is the original engine for the BMW G01 X3 30i, which makes it the straightforward choice. The third X3 was built 2017–2024, and the B46B20 was produced 2015–2026, 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 G01 X3 30i?

We do not have a B46B20 on the shelf for the G01 X3 30i 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 B48B20TU fit my BMW G01 X3 30i?

The B48B20TU is the original engine for the BMW G01 X3 30i, which makes it the straightforward choice. The third X3 was built 2017–2024, and the B48B20TU was produced 2018–2026, 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 G01 X3 30i?

We have 2 B48B20TU engines in stock, priced from 3.046,00 € to 4.795,00 €. Delivery to your door is included, and the engine carries a 12-month warranty when fitted by a qualified workshop. Add fitting labour and the parts you replace at the same time — seals, cooling parts and mounts — to estimate the total.

Will the B48B20B fit my BMW G01 X3 30i?

The B48B20B is the original engine for the BMW G01 X3 30i, which makes it the straightforward choice. The third X3 was built 2017–2024, and the B48B20B was produced 2019–2026, 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 G01 X3 30i?

We have 6 B48B20B engines from G01 donor cars, priced from 1.310,00 € to 3.241,00 €. Delivery to your door is included, and the engine carries a 12-month warranty when fitted by a qualified workshop. Add fitting labour and the parts you replace at the same time — seals, cooling parts and mounts — to estimate the total.

Engine swaps and upgrades for the X3 30i

These engines were fitted to other versions of the G01 at the factory, which makes them the most practical upgrades: the body was designed around them and many parts are shared.

Can I fit the B57D30 in my X3 30i?

It is a full conversion: the B57D30 runs on diesel and the B48B20B on petrol, so the fuel system, wiring, engine control unit, instrument coding and usually the gearbox change too. The gain is 7 hp and 220 Nm. In Germany and most of Europe an engine swap must be inspected and registered.

Fitting a replacement engine in the X3 30i

1. 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.
2. Replace the rear timing chain if in doubt. On engines with the chain at the gearbox end, chain work needs the engine out. If the history is unknown, replace the chain, guides and tensioner before fitting.
3. Prepare the turbo. Fit new oil feed and return seals, clean the intercooler and pipes of any oil or debris from the old engine, and prime the turbo with oil before starting.
4. Reset VANOS adaptations. Clear the VANOS adaptations so the ECU learns the camshaft positions of the new engine.
5. Teach the Valvetronic limit stops. Run the Valvetronic learning routine so the ECU knows the eccentric shaft limits.
6. 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.
7. 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.
8. 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.
9. 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.

The full fitting and first-start procedure.

Delivery, warranty and payment

Every X3 30i engine we sell is drained, sealed at each opening, strapped to a heat-treated pallet and shrink-wrapped before it leaves Hamburg. You receive photographs of the packed engine and a tracking number.

Door-to-door delivery is included to the address you give at checkout. Typical delivery takes three to five working days within Germany and neighbouring countries and five to ten working days to the rest of Europe and the UK.

Every engine carries a 12-month warranty on eligible internal failure when a qualified workshop fits it with new fluids and filters. Payment is by card, bank transfer or crypto; your invoice is emailed as soon as you order.

All G01 engines · B48 and B46 engine guide · B48 and B46 engine guide · BMW X3 30i engines for sale · Send us your VIN