BMW 520i (E39) engine: which one, problems and replacement

The BMW 520i in the fourth 5 Series generation (E39, built 1995–2004) was built with 2 different engines over its life: the M52B20 (150 hp, 1994–2000) and the M54B22 (170 hp, 2000–2006).

This guide tells you which engine your 520i has, what goes wrong with it, what a replacement costs from our stock and what else to plan for when you fit one.

• Generation: fourth 5 Series, 1995–2004
• Body styles: E39 (saloon, Touring)
• Engines: M52B20, M54B22
• Output: 150 hp and 170 hp
• Replacement engines in stock: 14 from 1.311,00 €

Which engine is in your 520i?

M52B20 in the 520i

The M52B20 was used in the E39 520i, built 1994–2000. It is a 2.0 L naturally aspirated petrol inline-6 with 150 hp and 190 Nm. Compared with the M54B22 (170 hp), it is the mildest.

Reading the code: M marks an M-series code, the naming BMW used for its engine families up to the early 2000s; 52 is the family number; B stands for petrol (from the German Benzin); 20 is the capacity in decilitres, so 2.0 litres.

M54B22 in the 520i

The M54B22 was used in the E39 520i, built 2000–2006. It is a 2.2 L naturally aspirated petrol inline-6 with 170 hp and 210 Nm. Compared with the M52B20 (150 hp), it is the strongest.

Reading the code: M marks an M-series code, the naming BMW used for its engine families up to the early 2000s; 54 is the family number; B stands for petrol (from the German Benzin); 22 is the capacity in decilitres, so 2.2 litres.

520i engines by model year

The engine changed 2 times during the E39 run, in 2000 and 2001. 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 520i

A replacement engine does not have to come from another 520i. 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.

M52B20: BMW E36 320i, BMW Z3 2.0.

M54B22: BMW E46 320i, BMW E60 520i, BMW Z4 2.2.

How to confirm your engine code

Because the 520i 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 520i engine problems

M52B20 (M52 family)

The M52B20 in the 520i shares the known weak points of the M52 family. Full M52 guide.

Nikasil bore wear. Early Nikasil engines run poorly when high-sulphur fuel damages the bore coating. Low compression and hard hot starts are the symptoms.

Cooling system. Plastic water pump impellers, thermostat housings and radiator necks crack.

VANOS seals and solenoids. Hardened seals cause rough idle and a loss of torque; double VANOS units also rattle.

DISA valve (M52TU). The flap inside the DISA valve can break and be drawn into the engine.

Crankcase ventilation. A blocked CCV causes oil consumption and leaks.

M54B22 (M54 family)

The M54B22 in the 520i shares the known weak points of the M54 family. Full M54 guide.

Crankcase ventilation (CCV). A failed CCV valve causes oil consumption, a whistle at idle, smoke and lean-running codes. It is the most common M54 fault.

DISA valve flap. The plastic flap inside the DISA valve can break and enter the engine.

Cooling system. Expansion tanks, thermostats and water pumps fail around 100,000 km.

Oil filter housing and valve cover gaskets. Both harden and leak oil onto the exhaust and alternator.

Oil consumption from piston rings. Some engines burn oil when rings stick, often after short-trip use.

Symptoms to watch for on the 520i

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.

Hard starting when warm and low compression. On engines with Nikasil bores, the bore coating may be damaged. A leak-down test confirms it.

Looking after the 520i engine

M52 engines

• Oil: 5W-30 or 5W-40 synthetic to BMW Longlife standard, about 6.5 litres with filter.
• Service interval: Oil every 10,000 to 15,000 km; VANOS seals and cooling every 100,000 km.
• Timing drive: Duplex lower and single upper chains at the front with hydraulic tensioner.
• Workshop notes: Ask whether the block is Nikasil or Alusil. Engines built from late 1998 use Alusil.

M54 engines

• Oil: 5W-30 BMW Longlife-01 synthetic, about 6.5 litres with filter.
• Service interval: Oil every 15,000 km or yearly; spark plugs every 100,000 km; cooling every 100,000 km.
• Timing drive: Duplex and single chains at the front, no scheduled replacement.
• Workshop notes: Change the CCV system and DISA valve before fitting a used M54. Both are cheap compared with an engine.

Buying a used engine for the 520i: checklist

1. 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.
2. 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.
3. 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.
4. 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.
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. 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.
7. 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.
8. 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.
9. Bore coating. Early engines with Nikasil bores can be damaged by high-sulphur fuel. A compression or leak-down test is the only reliable check; units with Alusil or iron bores are not affected.
10. Plastic cooling parts. Expansion tanks, thermostat housings and water pump impellers made of plastic crack with age. Plan to replace them when the engine is fitted.

BMW 520i replacement engine cost

We currently hold 14 520i engine engines. The cheapest is 1.311,00 €, the most expensive 3.103,00 €, and half of them cost less than 1.505,00 €.

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.

2 of these come from E39 donor cars, priced from 1.320,00 € to 1.492,00 €. 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 520i

These 520i units are in our Hamburg yard right now. Each listing shows real photographs of the engine you receive, its mileage and what is fitted.

BMW Z4 2.2 M54B22 Complete Engine1.505,00 €BMW E39 520i M54B22 Complete Engine1.492,00 €BMW E39 520i M52B20 Complete Engine1.320,00 €BMW 320i F30 M54B22 Engine 20131.661,00 €M54B22 Complete Engine BMW 520i G302.105,00 €BMW Z3 2.0 M52B20 Complete Engine1.311,00 €

BMW Z4 2.2 M54B22 Complete Engine — 1.505,00 €, reduced from 2.000,00 €. It comes from a recorded donor car, and 20 units are available. Ask the desk for compression figures or extra photographs before you order.

BMW E39 520i M54B22 Complete Engine — 1.492,00 €, reduced from 2.000,00 €. It comes from a recorded donor car, and 6 units are available. The listing shows every side of the engine and the fitted parts.

BMW E39 520i M52B20 Complete Engine — 1.320,00 €, reduced from 1.900,00 €. It comes from a recorded donor car, and 8 units are available. The listing shows every side of the engine and the fitted parts.

BMW 320i F30 M54B22 Engine 2013 — 1.661,00 €, reduced from 3.000,00 €. It comes from a 2013 donor car, and 25 units are available. Ask the desk for compression figures or extra photographs before you order.

M54B22 Complete Engine BMW 520i G30 — 2.105,00 €, reduced from 3.200,00 €. It comes from a recorded donor car, and 9 units are available. We can confirm fitment against your VIN the same day.

BMW Z3 2.0 M52B20 Complete Engine — 1.311,00 €, reduced from 1.900,00 €. It comes from a recorded donor car, and 27 units are available. Ask the desk for compression figures or extra photographs before you order.

Will it fit my 520i?

Will the M52B20 fit my BMW E39 520i?

Yes, the BMW E39 520i left the factory with the M52B20, so an M52B20 from another car is the direct replacement. The fourth 5 Series was built 1995–2004, and the M52B20 was produced 1994–2000, 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 E39 520i?

We have 1 M52B20 engine from E39 donor cars, priced from 1.320,00 €. 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 M54B22 fit my BMW E39 520i?

Yes, the BMW E39 520i left the factory with the M54B22, so an M54B22 from another car is the direct replacement. The fourth 5 Series was built 1995–2004, and the M54B22 was produced 2000–2006, 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 E39 520i?

We have 1 M54B22 engine from E39 donor cars, priced from 1.492,00 €. 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 520i

These engines were fitted to other versions of the E39 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 M57D30 in my 520i?

It is a full conversion: the M57D30 runs on diesel and the M54B22 on petrol, so the fuel system, wiring, engine control unit, instrument coding and usually the gearbox change too. The gain is 14 hp and 180 Nm. In Germany and most of Europe an engine swap must be inspected and registered.

Can I fit the M57D30OL in my 520i?

It is a full conversion: the M57D30OL runs on diesel and the M54B22 on petrol, so the fuel system, wiring, engine control unit, instrument coding and usually the gearbox change too. The gain is 14 hp and 180 Nm. In Germany and most of Europe an engine swap must be inspected and registered.

Can I fit the M54B25 in my 520i?

Yes, it is one of the more common upgrades. Both are petrol inline-6 engines, so the mounting points are similar, but the M54B25 needs its own wiring and engine control unit, the matching gearbox or clutch, and often a different sump, cooling and exhaust. The gain is 22 hp and 35 Nm. In Germany and most of Europe an engine swap must be inspected and registered.

Fitting a replacement engine in the 520i

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. Reset VANOS adaptations. Clear the VANOS adaptations so the ECU learns the camshaft positions of the new engine.
3. 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.
4. 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.
5. 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.
6. 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

Before a 520i 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.

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.

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.

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