BMW B47 engine report

BMW B47 · 1 Series (F20)
2.0 LDieselInline-42015–2019


BMW B47 · 1 Series (F20)
2.0 LDieselInline-42015–2019

74/100
[good]
Dependable, if the chain history checks out
Worth buying if the service history checks out.
Owners mention two things far more than the rest: timing chain stretch with worn guides, and coking around the EGR valve and swirl flaps.
Both are common enough that a full service history is worth more here than a low odometer reading. DPF clogging and failed regenerations sit in the same bracket, usually on cars that never left town, so one with motorway miles behind it is the safer buy. Heavy oil consumption and ringland failure turn up very rarely.
8 confirmed · sorted by severity
The cooler for the recirculated exhaust gas develops an internal leak. Coolant disappears with no visible drip, and the exhaust may smell sweet or smoke white. Left alone, it contaminates the intake and can overheat the engine.
Common · Manufacturing defect. Can destroy the engine if ignored. Not safely drivable.
3 owner reports back this, confidence 95/100.
Piston ringland cracking under high cylinder pressure/heat, common on tuned forced-induction engines.
Very rare · Design weakness. Does not normally destroy the engine. Not safely drivable.
1 owner report backs this, confidence 40/100.
Timing chain elongates or plastic guides wear prematurely, causing rattle, incorrect valve timing, or in severe cases chain failure.
Very common · Age-related wear. Does not normally destroy the engine. Still drivable.
21 owner reports back this, confidence 40/100.
Diesel particulate filter clogs, especially with short/urban trips that prevent regeneration, triggering warning lights or limp mode.
Common · Environmental. Does not normally destroy the engine. Still drivable.
10 owner reports back this, confidence 45/100.
Worn valve stem seals, piston rings, or a clogged PCV/oil separator system causing oil consumption above manufacturer spec.
Very rare · Age-related wear. Does not normally destroy the engine. Still drivable.
1 owner report backs this, confidence 40/100.
EGR valve, EGR cooler, or intake swirl flaps clog with carbon/soot, causing rough running or limp mode.
Very common · Expected maintenance. Can destroy the engine if ignored. Still drivable.
20 owner reports back this, confidence 40/100.
ECU hardware fault or injector wiring loom degradation causing misfires or no-start conditions.
Occasional · Manufacturing defect. Does not normally destroy the engine. Still drivable.
5 owner reports back this, confidence 40/100.
Crankshaft, camshaft, MAP, lambda/O2, or MAF sensor failure causing rough running, stalling, or incorrect fueling.
Occasional · Age-related wear. Does not normally destroy the engine. Still drivable.
6 owner reports back this, confidence 40/100.
0 of 7 checked
Updated 15 Sept 2026 · scoring v2.7
This report combines 70 owner posts, forum threads and official records. An issue only makes the list once the evidence is strong enough, an official recall on its own or several independent owner reports, and the score weighs how often each problem happens against how bad it is when it does.