BMW 3 Series N47
"Anyone who thinks the N47 snapping chain thing is exaggerated should see the yard full of F30's queued up waiting to get on the lift."
Power Variants
Recommendation
Don't pick an N47 based on the hp figure on the registration document. Pick it based on the engine build date (stamped on the block, or visible in the DDE via diagnostics), not the car's registration year. The highest timing chain risk falls on engines built between 1 March 2007 and 5 January 2009, regardless of output (163, 177 or 184hp). BMW never issued a legal recall for this in the UK/EU. It was a voluntary 'Quality Enhancement' programme that started in 2015 and was scaled back around 2016, with inconsistent coverage. Ask for written, dealer-stamped proof that the work was done, not just a verbal answer.
Known Issues
Rear Timing Chain FailureCRITICAL
The N47's timing chain is mounted at the rear of the engine, requiring near-full engine removal to service. Chain stretch, guide wear and tensioner failure are endemic, most severely on engines built between 1 March 2007 and 5 January 2009. Contrary to popular belief, this was never a legal recall in the UK/EU. BMW ran a voluntary 'Quality Enhancement' programme starting around March 2015, limited to specific VINs on a list, later scaled back around 2016 with inconsistent dealer-by-dealer coverage. Engines built after March 2011 received a revised crankshaft, chain guides and tensioner design, meaningfully reducing but not eliminating the risk. A snapped chain causes catastrophic engine destruction.
EGR Cooler Failure and Oil ContaminationHIGH
The EGR cooler is prone to internal leaks, causing coolant mixing with exhaust gases and leading to oil consumption and fault code 290900. Early N47s use a pneumatic EGR valve, later units use a fully electric valve. In severe cases, cracked EGR coolers have led to intake tube melting and, rarely, engine bay fires, which is the root cause behind BMW's much larger 2018 global recall (see Recalls section).
Swirl Flap Actuator and Broken LeverHIGH
The intake manifold swirl flaps are operated by a mechanical linkage that is prone to breaking. A broken lever generates fault code 2C3200. If a flap detaches entirely, it can be ingested by the engine causing severe internal damage.
Glow Plug FailureMODERATE
Glow plug failure is commonly reported on the N47, particularly as mileage increases. DIY replacement is feasible and frequently performed. Failed glow plugs cause hard cold starts and increased emissions.
Oil Pressure Warning and ConsumptionMODERATE
Intermittent oil pressure warnings are reported across the N47 platform. Causes include oil pressure switch failure and genuine oil consumption linked to EGR cooler degradation or worn piston rings.
Turbo Wastegate Return Spring DegradationMODERATE
The return spring on the sequential turbo's wastegate was not originally lubricated or covered, causing early degradation. This leaves the wastegate partially or fully open, reducing boost and increasing fuel consumption by 30 to 50 percent. BMW engineers internally described this as a known fault with an improved replacement spring, but BMW has not offered compensation for the resulting excess fuel consumption to affected owners.
Automatic Transmission Mechatronic / Manual Reverse Gear FailureHIGH
ZF 6HP19/6HP21 automatic gearboxes fitted behind the N47 are prone to mechatronic (valve body) unit failure, forcing the transmission into limp mode. Separately, manual GS6-45DZ gearboxes fitted to EfficientDynamics variants have a widely reported weak reverse gear synchro, with multiple owners reporting total loss of reverse gear.
Official Recalls
EGR cooler can crack internally, leading to coolant mixing with exhaust and, in rare cases, intake tube melting or engine bay fire. BMW issued a global recall covering approximately 1.6 million vehicles in 2018.
BMW recalled certain 2007-2013 3 Series and 2008-2013 1 Series for a crankcase ventilation (PCV) related emissions system fault that could cause oil ingestion or emissions non-compliance.
Buying Checklist
Service Reality
Strong Points
Also Found In
Time Bomb Parts Inspect Proactively
Tuning Risk If This Example Has Been Modified
HIGHA chip tune on this ECU (DDE) can generally be flashed back to a stock-reading map. DPF and EGR work is more nuanced on this specific engine than on some others: some specialist tuners explicitly recommend leaving the DPF and EGR in place and instead disabling the EGR via software (closed permanently) while leaving the DPF functional, arguing that full physical DPF removal is illegal for road use and that some tuners who push full deletes are doing so to profit from selling the removed DPF internals. This means the presence of tuning does not automatically imply a full delete, and conversely a clean-scanning car may still have had DPF or EGR software manipulation that only shows up under close inspection or with manufacturer-level diagnostic tools. Separately, and specific to this engine: reputable tuners state they will not remap a car showing timing chain rattle or noise, since increased load is known to worsen that pre-existing risk, so the presence of a tune on a car is not itself informative about chain condition, and a seller having 'passed' a pre-tune check by one shop does not guarantee another shop performed the same diligence.
Specialist guidance for this specific engine is explicit that tuning should only be done on a demonstrably healthy example, with timing chain, turbo, and EGR condition checked first; a tune applied without that check is considered materially riskier, not because the tune itself damages these parts, but because it adds load on top of components that may already be marginal. This is a meaningfully different pattern from most other engines in this database, where supporting mods are about handling more power; here, the equivalent 'supporting work' is a pre-tune health check and address of the chain/turbo/EGR before or alongside a remap.
DPF and EGR deletes are commonly discussed and performed on this engine, but community opinion is more divided here than on some other diesels: some specialist tuners actively discourage a full physical DPF delete (noting it is illegal for road use) in favor of a software-only EGR-closed approach that keeps the DPF working. Either way, a deleted or non-functional DPF/EGR will fail an MOT/roadworthiness emissions inspection in the UK/EU, and a straight-piped DPF may not be obvious without a physical underside inspection since a properly executed software-side change can produce a clean OBD scan.
This profile reflects consensus from Baby BMW Forum, BimmerForums UK, F30POST's N47/N57 diesel subforum, and specialist commentary (BSG Automotive, Apex Auto Parts, Star Garage, BW Chiptune), not manufacturer-confirmed limits. The timing chain failure rate and its relationship to specific production years is debated in the community rather than precisely quantified by BMW. Treat any example of this engine, tuned or not, as needing a careful cold-start listen for chain rattle as part of a full pre-purchase inspection, alongside a physical underside check for DPF/EGR presence and a turbo health check, rather than relying on an OBD scan alone.
Buying Advice
The BMW N47 is a fundamentally capable diesel engine held hostage by its rear-mounted timing chain, a design that turns a routine maintenance item into a near-engine-out job costing €2,000 to €5,000. The single most important thing to check is engine build date, not the hp badge. Engines built between 1 March 2007 and 5 January 2009 carry the highest risk, and BMW's fix was a voluntary Quality Enhancement programme (not a legal recall in the UK/EU), started in 2015 and inconsistently applied. Budget at least €1,500 to €2,500 as a contingency fund for chain, EGR, and swirl flap work on any car without recent documented repairs. If all major issues have been addressed with receipts, the N47 can be a rewarding ownership experience, but buying one blind, purely on the hp figure, is genuinely high risk.
Community Sentiment
Predominantly negative due to timing chain anxiety. Owners who have proactively replaced the chain report satisfaction, but the community is saturated with horror stories of snapped chains and destroyed engines. The phrase 'has the chain been done?' is the first question asked in every N47 buying thread. A recurring secondary frustration is BMW's own terminology: many owners refer to it as 'a recall' when discussing it, only to be corrected that it was technically a voluntary goodwill programme, a distinction owners view as something BMW leaned on to limit liability.
Frequently Asked Questions
❯Is the N47 reliable?
The BMW 3 Series N47 has a reliability score of 38/100, rated "RISKY". Ticking time bomb, chain kills engines
❯What problems does the N47 have?
The most frequently reported issues are Rear Timing Chain Failure, EGR Cooler Failure and Oil Contamination, Swirl Flap Actuator and Broken Lever, Glow Plug Failure, among others. See the Known Issues section above for symptoms, affected mileage, and repair costs.
❯Does the N47 have rear timing chain failure problems?
Yes, this is a documented issue on the N47, typically appearing around 80,000-200,000 km. The N47's timing chain is mounted at the rear of the engine, requiring near-full engine removal to service. Chain stretch, guide wear and tensioner failure are endemic, most severely on engines built between 1 March 2007 and 5 January 2009. Contrary to popular belief, this was never a legal recall in the UK/EU. BMW ran a voluntary 'Quality Enhancement' programme starting around March 2015, limited to specific VINs on a list, later scaled back around 2016 with inconsistent dealer-by-dealer coverage. Engines built after March 2011 received a revised crankshaft, chain guides and tensioner design, meaningfully reducing but not eliminating the risk. A snapped chain causes catastrophic engine destruction. Typical repair cost: €2,000-5,000. DIY difficulty: Expert only, requires engine removal.
❯Does the N47 have egr cooler failure and oil contamination problems?
Yes, this is a documented issue on the N47, typically appearing around 100,000-200,000 km. The EGR cooler is prone to internal leaks, causing coolant mixing with exhaust gases and leading to oil consumption and fault code 290900. Early N47s use a pneumatic EGR valve, later units use a fully electric valve. In severe cases, cracked EGR coolers have led to intake tube melting and, rarely, engine bay fires, which is the root cause behind BMW's much larger 2018 global recall (see Recalls section). Typical repair cost: €500-1,500. DIY difficulty: Moderate, accessible but requires cooling system bleed.
❯Does the N47 have swirl flap actuator and broken lever problems?
Yes, this is a documented issue on the N47, typically appearing around 80,000-180,000 km. The intake manifold swirl flaps are operated by a mechanical linkage that is prone to breaking. A broken lever generates fault code 2C3200. If a flap detaches entirely, it can be ingested by the engine causing severe internal damage. Typical repair cost: €300-1,200. DIY difficulty: Moderate, intake manifold removal required.
❯Does the N47 have glow plug failure problems?
Yes, this is a documented issue on the N47, typically appearing around 80,000-150,000 km. Glow plug failure is commonly reported on the N47, particularly as mileage increases. DIY replacement is feasible and frequently performed. Failed glow plugs cause hard cold starts and increased emissions. Typical repair cost: €150-400. DIY difficulty: Moderate, risk of snapping plugs in head if not soaked first.
❯Does the N47 have oil pressure warning and consumption problems?
Yes, this is a documented issue on the N47, typically appearing around 100,000-220,000 km. Intermittent oil pressure warnings are reported across the N47 platform. Causes include oil pressure switch failure and genuine oil consumption linked to EGR cooler degradation or worn piston rings. Typical repair cost: €100-800. DIY difficulty: Low to moderate, switch replacement is simple, deeper causes require investigation.
❯Does the N47 have turbo wastegate return spring degradation problems?
Yes, this is a documented issue on the N47, typically appearing around 100,000-180,000 km. The return spring on the sequential turbo's wastegate was not originally lubricated or covered, causing early degradation. This leaves the wastegate partially or fully open, reducing boost and increasing fuel consumption by 30 to 50 percent. BMW engineers internally described this as a known fault with an improved replacement spring, but BMW has not offered compensation for the resulting excess fuel consumption to affected owners. Typical repair cost: €80-250. DIY difficulty: Low, spring is accessible without major disassembly.
❯Is the N47 worth buying used?
The BMW N47 is a fundamentally capable diesel engine held hostage by its rear-mounted timing chain, a design that turns a routine maintenance item into a near-engine-out job costing €2,000 to €5,000. The single most important thing to check is engine build date, not the hp badge. Engines built between 1 March 2007 and 5 January 2009 carry the highest risk, and BMW's fix was a voluntary Quality Enhancement programme (not a legal recall in the UK/EU), started in 2015 and inconsistently applied. Budget at least €1,500 to €2,500 as a contingency fund for chain, EGR, and swirl flap work on any car without recent documented repairs. If all major issues have been addressed with receipts, the N47 can be a rewarding ownership experience, but buying one blind, purely on the hp figure, is genuinely high risk.
❯Should I buy a BMW 3 Series with the N47 engine?
Don't pick an N47 based on the hp figure on the registration document. Pick it based on the engine build date (stamped on the block, or visible in the DDE via diagnostics), not the car's registration year. The highest timing chain risk falls on engines built between 1 March 2007 and 5 January 2009, regardless of output (163, 177 or 184hp). BMW never issued a legal recall for this in the UK/EU. It was a voluntary 'Quality Enhancement' programme that started in 2015 and was scaled back around 2016, with inconsistent coverage. Ask for written, dealer-stamped proof that the work was done, not just a verbal answer.
❯What should I check before buying a used N47?
Before buying, check: Cold-start the engine from fully cold and listen for at least 2 minutes for any metallic rattle, ticking, or washing-machine swooshing noise from the rear of the engine; Ask for the engine build date (stamped on block, or visible in the DDE via ISTA), not the car's registration date. The highest-risk window is 03/2007 to 01/2009; Ask specifically whether the Quality Enhancement (not 'recall') was completed, and request written or dealer-stamped confirmation, not a verbal answer; Scan the full fault memory with ISTA or INPA. Check codes 290900 (EGR cooler), 2C3200 (swirl flap lever), EGS transmission codes, and any timing or VANOS codes; Check VIN against BMW's 2018 EGR cooler recall database.
❯How many km will a N47 last?
There's no fixed mileage limit, it depends on maintenance. The parts worth budgeting for proactively are: Rear timing chain kit (chain, guides, tensioner) (100,000-150,000 km), Swirl flap assembly / intake manifold (80,000-160,000 km), EGR cooler (100,000-200,000 km), Turbo wastegate return spring (100,000-180,000 km). Engines that clear these checkpoints with documented maintenance commonly continue well beyond typical ownership periods.
❯Is there a recall for the egr cooler, cracking / coolant leak / fire risk on the N47?
EGR cooler can crack internally, leading to coolant mixing with exhaust and, in rare cases, intake tube melting or engine bay fire. BMW issued a global recall covering approximately 1.6 million vehicles in 2018. Remedy: Inspection and, where necessary, EGR cooler replacement at authorised BMW dealer. Check VIN against BMW's 2018 recall database
❯Is there a recall for the crankcase pcv emissions system on the N47?
BMW recalled certain 2007-2013 3 Series and 2008-2013 1 Series for a crankcase ventilation (PCV) related emissions system fault that could cause oil ingestion or emissions non-compliance. Remedy: Replacement of affected PCV components at authorised BMW dealer; check VIN for applicability
❯How much does it cost to maintain a N47?
Estimated ownership cost is €1,500-4,500 over 3 years depending on timing chain and EGR status at purchase, based on known issues and typical service needs.
❯What is the real-world fuel consumption of the N47?
Owners report real-world fuel consumption of around 6 L/100km.
❯What oil should I use in a N47, and how often?
Community-reported real-world usage suggests changing oil every 10,000 km using BMW Longlife-04 5W-30 fully synthetic (e.g., Castrol Edge 5W-30 LL or Mobil 1 ESP 5W-30), often more conservative than the official service schedule.
❯Is it safe to tune or remap the N47?
The N47 is commonly modified, with a high risk level when pushed beyond stock. Typical weak points under tuning: Timing chain and tensioner, DPF and EGR system, Turbocharger (variable geometry), Injectors and EGR-related carbon buildup. Emissions-delete modification is a known risk area on this engine.
❯What other cars use the N47 engine?
The N47 is also found in: BMW 1 Series E81/E82/E87/E88 116d/118d/120d, BMW 3 Series E90/E91/E92/E93 318d/320d, BMW 5 Series F10/F11 518d/520d, BMW X1 E84 18d/20d, BMW 3 Series F30 318d/320d (N47TU).
❯Why does the N47 have a bad reputation?
Ticking time bomb, chain kills engines The biggest recurring complaint is Rear Timing Chain Failure. Predominantly negative due to timing chain anxiety. Owners who have proactively replaced the chain report satisfaction, but the community is saturated with horror stories of snapped chains and destroyed engines. The phrase 'has the chain been done?' is the first question asked in every N47 buying thread. A recurring secondary frustration is BMW's own terminology: many owners refer to it as 'a recall' when discussing it, only to be corrected that it was technically a voluntary goodwill programme, a distinction owners view as something BMW leaned on to limit liability.