BMW Z4 M40i (G29) engine: which one, problems and replacement

The BMW Z4 M40i in the third Z4 generation (G29, built 2018–) was built with 2 different engines over its life: the B58B30 (340 hp, 2015–2026) and the B58B30M1 (374 hp, 2019–2026).

This guide tells you which engine your Z4 M40i has, what goes wrong with it, what a replacement costs from our stock and what else to plan for when you fit one.

• Generation: third Z4, 2018–
• Body styles: G29 (roadster)
• Engines: B58B30, B58B30M1
• Output: 340 hp and 374 hp
• Replacement engines in stock: 452 from 3.606,00 €

Which engine is in your Z4 M40i?

B58B30 in the Z4 M40i

The B58B30 was used in the G29 Z4 M40i, built 2015–2026. It is a 3.0 L turbocharged petrol inline-6 with 340 hp and 500 Nm. Compared with the B58B30M1 (374 hp), it is the mildest.

Reading the code: B marks a B-series code, BMW's modular engine family introduced from 2013 with 500 cc per cylinder; 58 is the family number; B stands for petrol, longitudinal installation for rear-drive and xDrive cars; 30 is the capacity in decilitres, so 3.0 litres.

B58B30M1 in the Z4 M40i

The B58B30M1 was used in the G29 Z4 M40i, built 2019–2026. It is a 3.0 L turbocharged petrol inline-6 with 374 hp and 500 Nm. Compared with the B58B30 (340 hp), it is the strongest.

Reading the code: B marks a B-series code, BMW's modular engine family introduced from 2013 with 500 cc per cylinder; 58 is the family number; B stands for petrol, longitudinal installation for rear-drive and xDrive cars; 30 is the capacity in decilitres, so 3.0 litres; M1 identifies the version or output stage.

Other cars with the same engine as the Z4 M40i

A replacement engine does not have to come from another Z4 M40i. 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.

B58B30: BMW F30 340i, BMW G20 M340i, BMW G30 540i, BMW G05 X5 40i, Supra 3.0.

B58B30M1: BMW G20 M340i, Toyota A90 Supra.

How to confirm your engine code

Because the Z4 M40i 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 Z4 M40i engine problems

The B58B30 and B58B30M1 in the Z4 M40i share the known weak points of the B58 family. Full B58 guide.

Coolant leaks. Expansion tanks and coolant lines leak.

Oil filter housing. The plastic oil filter housing can leak.

PCV valve. The PCV in the valve cover can fail.

Symptoms to watch for on the Z4 M40i

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 Z4 M40i engine

• Oil: 0W-30 BMW Longlife-01 or 17 FE+, about 6.5 litres.
• Service interval: Oil every 15,000 km or yearly.
• Timing drive: Timing chain at the rear (gearbox end).
• Workshop notes: Check the version (B58B30M0, M1 or TU) before ordering.

Buying a used engine for the Z4 M40i: checklist

1. 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.
2. 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.
3. 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.
4. 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.
5. 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.
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 Z4 M40i replacement engine cost

Across 452 Z4 M40i engine units in our stock today, prices start at 3.606,00 € and reach 7.976,00 €. The median — the price in the middle of the range — is 5.903,00 €.

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.

Z4 M40i engine prices by model year

Engines from 2015–2019 have a median of 5.518,00 €, while units from 2025–2029 sit at 6.613,00 €. Newer engines usually cost more because they come from younger donor cars with lower mileage and later updates.

Z4 M40i 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.

2 of these come from G29 donor cars, priced from 3.606,00 € to 7.563,00 €. 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 Z4 M40i

These Z4 M40i 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 G11 740i B58B30 Engine 2016, 56,300 km5.007,00 €BMW G22 M440i B58B30M1 Engine 2020, 24,100 km5.776,00 €BMW G20 M340i B58B30M1 Engine 2019, 64,400 km6.578,00 €BMW G01 X3 M40i B58B30M1 Engine 2021, 160,300 km6.029,00 €BMW F30 340i B58B30 Engine 2018, 145,400 km5.070,00 €BMW F30 340i B58B30 Engine 2018, 19,300 km5.231,00 €BMW G11 740i B58B30 Engine 2015, 147,600 km5.651,00 €BMW G01 X3 M40i B58B30M1 Engine 2025, 176,900 km7.803,00 €BMW G20 M340i B58B30M1 Engine 2023, 181,100 km7.427,00 €BMW G11 740i B58B30 Engine 2016, 46,900 km4.812,00 €BMW A90 Supra B58B30M1 Engine 2025, 172,100 km7.783,00 €BMW G11 740i B58B30 Engine 2018, 161,100 km4.680,00 €

BMW G11 740i B58B30 Engine 2016, 56,300 km — 5.007,00 €, reduced from 5.650,00 €. It comes from a 2016 donor car with 56,300 km, and 6 units are available. We can confirm fitment against your VIN the same day.

BMW G22 M440i B58B30M1 Engine 2020, 24,100 km — 5.776,00 €, reduced from 6.850,00 €. It comes from a 2020 donor car with 24,100 km, and 7 units are available. We can confirm fitment against your VIN the same day.

BMW G20 M340i B58B30M1 Engine 2019, 64,400 km — 6.578,00 €, reduced from 8.050,00 €. It comes from a 2019 donor car with 64,400 km, and 25 units are available. Ask the desk for compression figures or extra photographs before you order.

BMW G01 X3 M40i B58B30M1 Engine 2021, 160,300 km — 6.029,00 €, reduced from 6.900,00 €. It comes from a 2021 donor car with 160,300 km, and 18 units are available. We can confirm fitment against your VIN the same day.

BMW F30 340i B58B30 Engine 2018, 145,400 km — 5.070,00 €, reduced from 6.200,00 €. It comes from a 2018 donor car with 145,400 km, and 22 units are available. Ask the desk for compression figures or extra photographs before you order.

BMW F30 340i B58B30 Engine 2018, 19,300 km — 5.231,00 €, reduced from 5.900,00 €. It comes from a 2018 donor car with 19,300 km, and 9 units are available. We can confirm fitment against your VIN the same day.

BMW G11 740i B58B30 Engine 2015, 147,600 km — 5.651,00 €, reduced from 6.250,00 €. It comes from a 2015 donor car with 147,600 km, and 17 units are available. The listing shows every side of the engine and the fitted parts.

BMW G01 X3 M40i B58B30M1 Engine 2025, 176,900 km — 7.803,00 €, reduced from 8.700,00 €. It comes from a 2025 donor car with 176,900 km, and 12 units are available. The listing shows every side of the engine and the fitted parts.

BMW G20 M340i B58B30M1 Engine 2023, 181,100 km — 7.427,00 €, reduced from 8.650,00 €. It comes from a 2023 donor car with 181,100 km, and 21 units are available. We can confirm fitment against your VIN the same day.

BMW G11 740i B58B30 Engine 2016, 46,900 km — 4.812,00 €, reduced from 6.200,00 €. It comes from a 2016 donor car with 46,900 km, and 27 units are available. Ask the desk for compression figures or extra photographs before you order.

BMW A90 Supra B58B30M1 Engine 2025, 172,100 km — 7.783,00 €, reduced from 8.600,00 €. It comes from a 2025 donor car with 172,100 km, and 24 units are available. We can confirm fitment against your VIN the same day.

BMW G11 740i B58B30 Engine 2018, 161,100 km — 4.680,00 €, reduced from 5.950,00 €. It comes from a 2018 donor car with 161,100 km, and 9 units are available. Ask the desk for compression figures or extra photographs before you order.

Will it fit my Z4 M40i?

Will the B58B30 fit my BMW G29 Z4 M40i?

For the BMW G29 Z4 M40i, the B58B30 is the factory engine and the one to order. The third Z4 was built 2018–, and the B58B30 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 G29 Z4 M40i?

We have 2 B58B30 engines from G29 donor cars, priced from 3.606,00 € to 7.563,00 €. 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 B58B30M1 fit my BMW G29 Z4 M40i?

For the BMW G29 Z4 M40i, the B58B30M1 is the factory engine and the one to order. The third Z4 was built 2018–, and the B58B30M1 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 G29 Z4 M40i?

We have 1 B58B30M1 engine from G29 donor cars, priced from 3.606,00 €. 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.

Fitting a replacement engine in the Z4 M40i

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.

Z4 M40i engine questions

How much does a used BMW B58B30M1 engine cost?

A used BMW B58B30M1 engine in our yard usually costs between 5.200 € and 7.950 €. 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 B58 Engines · Search B58B30M1 in the shop

How much is a replacement B58B30M1 engine for a BMW G30 M550i?

A used B58B30M1 for the BMW G30 M550i costs from about 5.200 € to 7.950 € 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 B58B30M1 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 B58 Engines · Search B58B30M1 in the shop

What is the BMW B58B30M1 engine?

The BMW B58B30M1 is a 3.0 liter (2,998 cc) petrol engine from the B58 family. It has an inline 6, DOHC, 24 valve layout with a twin-scroll turbocharger, and makes 275 kW (374 HP) with 500 Nm of torque. BMW built it from 2019 to 2026 and it meets the Euro 6 emission standard.

You find the B58B30M1 in the BMW G20 M340i, BMW G22 M440i, BMW G30 M550i, BMW G01 X3 M40i, BMW G05 X5 xDrive40i and BMW G42 M240i. What we list: BMW B58 3.0 turbo petrol engines for 340i, M340i, 540i and X5 40i.

At Autowerke Engines every B58B30M1 is a real used engine from our yard in Hamburg. 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. 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 B58 Engines · Search B58B30M1 in the shop

Delivery, warranty and payment

Before a Z4 M40i 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.

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 G29 engines · B58 engine guide · Send us your VIN