The B38 is known to suffer from timing chain stretch, mirroring a similar issue found in its diesel sibling the B47. A stretched or failed timing chain can cause catastrophic engine failure if the chain snaps. This is widely regarded as the single biggest reliability concern on this engine.
Rattling noise on cold start
Poor engine performance
Check engine light
Rough idle
Engine misfires
DIY: Expert
Water Pump Failure€400-900 · 80,000-150,000 kmHIGH
The water pump is a noted weak point on the B38, with failures reported leading to overheating and poor heater performance. Early replacement is recommended as preventative maintenance.
A DVSA recall was issued covering almost 35,000 BMW and MINI vehicles for potential EGR cooler leaks. EGR cooler failure can introduce coolant into the intake or exhaust system, causing running issues and potential damage.
White smoke from exhaust
Coolant loss with no visible external leak
Rough running
Overheating
DIY: Intermediate
Intercooler and Boost Pipe Integrity€100-400 · 60,000-120,000 kmLOW
Boost pressure pipes and intercooler connections can develop splits or loose fittings over time, causing reduced performance and potential fault codes. Pre-purchase inspection of all boost-side pipework is recommended.
Loss of power
Boost pressure faults
Hissing sound under acceleration
Increased fuel consumption
DIY: Beginner
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Buying Checklist
Cold-start the engine and listen carefully for any timing chain rattle in the first 30 seconds — walk away if present
Verify the DVSA EGR cooler recall has been completed using the VIN on BMW's recall checker
Request full BMW service history and confirm oil changes were done at or under 10,000 km intervals
Inspect all intercooler boost pipes and connections by hand for splits, cracks, or loose clamps
Check coolant level and condition — milky or low coolant may indicate water pump or EGR cooler failure
Run a BMW ISTA diagnostic scan to check for stored fault codes, timing chain deviation data, and any pending system warnings
Service Reality
Community oil interval10,000 km
Oil specificationBMW Longlife-04 5W-30 or 0W-30 (community strongly recommends shorter intervals than BMW's CBS system suggests given timing chain sensitivity)
Est. ownership cost (2yr)€1,200–4,500 over 3 years depending on whether timing chain and water pump work is required
Real mix fuel consumptionNo data
Also Found In
BMW 116i F20/F21BMW 118i F20/F21BMW 218i F22/F23BMW 316i F30BMW 318i F30MINI Cooper F55/F56BMW X1 sDrive18i F48
Buying Advice
The B38A15 is a capable modern turbo three-cylinder but carries a meaningful timing chain risk that must be treated as the primary concern on any used purchase. Cold-start rattle is a red flag that should end negotiations immediately. Always insist on a full BMW ISTA scan before purchase and budget for timing chain inspection or replacement if the car is over 80,000 km. Buyers who go in with eyes open, a pre-purchase inspection, and a contingency fund for chain work can still find usable examples — but this is not a set-and-forget engine.