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B-Class

2 generations · Select a generation to see engines

Which Mercedes Benz B-Class engine is the most reliable? See common problems, reviews and reliability verdicts across generations and engines.

Frequently asked questions

Which Mercedes Benz B-Class engine is the most reliable?

1.7 / 2.0 petrol (M266) (B-Class (W245)) — Maint. Sensitive verdict. The W245 shares the A-Class M266 petrols — simple, reliable engines, with the 2.0 (B200, incl. turbo) the better-matched choice for the taller, heavier B-Class body. Main niggles are ignition coils, plugs and the odd injector/sensor causing misfires and rough idle; prefer a 2008+ car with the early faults sorted. Note the 2.0 is 2,034cc (over 2.0L for tax in some countries). A dependable, low-drama people-carrier engine.

Which Mercedes Benz B-Class engines should you avoid?

None of the Mercedes Benz B-Class engines listed are rated "Problematic" or "Avoid" — but always check the service history before buying.

What are the most common Mercedes Benz B-Class problems?

The most commonly reported problems across all Mercedes Benz B-Class generations and engines: Coil / plug / injector faults, DPF clogging (short trips), Injector / EGR wear, Timing chain wear (early), Intake carbon (DI).