The N47's timing chain is mounted at the rear of the engine, meaning the engine must be removed for replacement. The chain, guides, and tensioners are prone to premature wear and outright snapping. This is the N47's defining and most catastrophic failure mode, widely documented across all chassis variants. Pre-2011 units are worst affected but post-2011 F20 units are not immune. A snapped chain typically means total engine destruction.
Rattling noise on cold start from rear of engine
Rattling that increases with RPM
Check engine light with timing-related codes
Engine failure to start after chain snaps
Catastrophic engine noise followed by sudden cut-out
The Bosch CP4.1 HPFP fitted to the N47 is known to fail, generating metal shavings that contaminate the entire fuel system including injectors, fuel rail, and lines. BMW issued a recall (21V-586) and extended warranty coverage for HPFP issues on N47 and N57 engines. Failure typically results in a no-start condition and can require full fuel system replacement if contamination is widespread.
Car cranks but will not start
Loss of power on motorway
Metal debris found in fuel filter
Injector fouling or failure shortly after pump failure
DIY: Advanced — specialist recommended due to contamination risk
EGR Cooler Leaks and EGR System Failure€400-1,200 · 100,000-200,000 kmHIGH
EGR cooler leaks on N47 engines have been significant enough to trigger a DVSA recall covering nearly 35,000 BMW and MINI vehicles. EGR valves also clog and fail, causing hesitation at constant cruise speeds around 1,500 rpm and triggering fault codes. EGR-related oil consumption has also been reported in conjunction with cooler failure.
Hesitation or surging at constant throttle around 1,500 rpm
Crankshaft / Rod Bearing Wear at High Mileage€800-2,500 · 250,000-350,000 kmHIGH
At very high mileage, rod bearing failure has been reported on N47 engines, presenting as severe engine knock and metal scraping. This is often connected to extended oil change intervals or oil starvation events. Multiple forum reports document sudden onset at 300,000+ km.
Sudden severe engine knocking
Vibration through the cabin
Metal scraping sound increasing with RPM
Oil pressure warning light
DIY: Expert only — engine stripdown required
Dual Mass Flywheel (DMF) Wear€700-1,500 · 150,000-250,000 kmMODERATE
The DMF on N47 manual variants is a known wear item. It is commonly replaced at the same time as the timing chain because engine removal is required for both jobs, making combined replacement highly cost-effective. Failure causes judder on take-off and clutch-related vibration.
Judder on clutch engagement at low speed
Rattling at idle in gear with clutch engaged
Vibration at low RPM under load
DIY: Expert only — engine removal required if done alongside chain
Oil Consumption€50-200 · 100,000-200,000 kmLOW
Some N47 owners report elevated oil consumption, particularly on higher mileage units. This is linked in some cases to EGR cooler degradation. Regular oil level checks between service intervals are recommended.
Oil level dropping between services
Occasional blue-tinged exhaust smoke
DIY: Low — monitoring only
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Buying Checklist
Cold-start the engine from fully cold and listen for any rear-of-engine rattle for at least 60 seconds — walk away if any chain noise is present
Check HPFP recall (21V-586) and EGR cooler recall completion status using the VIN on BMW's recall portal before viewing
Pull the fuel filter and inspect for metal shavings — any metallic debris means the fuel system is contaminated and the car is a write-off financially
Request full service history and verify oil changes were done at no more than 10,000 km intervals with correct BMW LL-04 spec oil
Scan with ISTA or INPA for live and stored fault codes — pay particular attention to EGR, fuel pressure, and timing-related codes
On manual gearbox cars, test clutch engagement for judder and ask whether DMF has been replaced — if timing chain work was done without DMF replacement, query why
Est. ownership cost (2yr)€1,500-4,500 per year depending on mileage and whether timing chain work has already been completed — budget separately for chain replacement if history is unknown
Real mix fuel consumptionNo data
Also Found In
BMW 318d / 320d / 330d (E90/E91/E92)BMW 518d / 520d / 525d (F10/F11)BMW X1 18d / 20d (E84)BMW X3 20d (F25)BMW 1 Series 116d / 118d / 120d (E81/E82/E87/E88)BMW 3 Series GT (F34)Mini Cooper SD (R56/R60)
Buying Advice
The BMW N47 in the F20 120d is a capable and torquey engine, but it carries serious structural risk centred on its rear-mounted timing chain and the Bosch CP4.1 fuel pump. Any used example must be purchased with a known, documented timing chain history or a substantial budget — expect €2,000-5,000 for a full chain replacement including labour for engine removal. Always verify both the HPFP and EGR cooler recalls have been completed using the VIN before committing. If the service history is incomplete, the timing chain noise test on cold start is non-negotiable — any rattle means walk away immediately.
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