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Engines · BMW

BMW B47 diesel common problems

The B47 is BMW's 2.0 four-cylinder turbodiesel, introduced in 2014 to replace the N47, with later versions gaining twin turbos and mild-hybrid assistance. It powers the 118d to 125d, 318d to 325d, 520d and the four-cylinder diesel X1, X3, X4 and X5, as well as MINI Cooper D and SD models, and it has a good reputation. Its timing chain has proved far more durable than the N47's.

Common problems and what to look for on the B47

The known issues most worth checking when you view a car with this engine. None of them means a car is a bad buy, but they're worth knowing about before you buy, and a good history often shows they've been dealt with.

  1. EGR cooler recalls

    What to look for: Ask a BMW dealer to check the car by its VIN (on the V5C) and confirm that all EGR cooler recall work has been done, including any later campaign. On the drive, note any loss of power, a burning smell, or a low coolant warning.

    Why it matters: The cooler in the exhaust gas recirculation system can leak coolant internally, and in rare cases the residue mixed with soot can catch fire. Earlier B47 cars were covered by BMW's 2018 and 2019 UK recalls (for example the X5 25d and four-cylinder models built up to 2017), and further campaigns followed from 2020, including one announced in 2024 that reached cars built up to 2022, with an improved cooler. A car fixed once may need the newer part. It is a free fix at a dealer.

  2. Particulate filter and short trips

    What to look for: Ask how the car has been used. Look for a particulate filter warning on the dashboard and note any loss of power on the drive. A car with a record of regular longer runs is the better sign.

    Why it matters: The diesel particulate filter has to get hot to clean itself, which only happens on a longer run. Cars driven mostly in town can block it, which shows as warnings and reduced power. A long drive often clears a partly blocked filter; a fully blocked one needs a forced clean or replacement. On a car that mostly does short trips, a petrol may suit better.

  3. Timing chain wear at very high mileage

    What to look for: Start the engine from cold with the bonnet open and listen for a rattle or ticking from the engine that lasts beyond the first few seconds, including from the back of the engine near the bulkhead. Ask for the oil change record.

    Why it matters: Like the N47, the B47 has its timing chain at the gearbox end of the engine, but the design was revised and chain trouble is far less frequent. Wear has been seen mainly at very high mileage, mostly where oil changes have been stretched. A quiet engine with a full history is in a good position.

More known issues, covered in the full guide for each car

  • Turbo wear where oil changes were skipped

Cars with the B47

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General points for the engine, last checked October 2026. Every car is different, so treat this as a guide to what to look at, not a verdict on any car. CrankSight is independent and has no connection with any manufacturer.