Mercedes-Benz M266
inline-4 · naturally aspirated · petrol · 2004–2012
Also known as: m266, 1.5 a-class, 1.7 a-class, 2.0 a-class, m266 e 20, a170 engine, m166
The naturally aspirated four of the W169 A-Class and W245 B-Class, in 1.5, 1.7 and 2.0 litre forms — the last of Mercedes-Benz's sandwich-floor small cars before the platform changed completely.
It is a simple, port-injected, chain-driven engine, and its own faults are modest. The complaints that dominate these cars are the CVT rather than the engine: the autotronic transmission behind many of them produces flaring, hesitation and loss of drive that arrive described as engine problems. Separate an engine-speed symptom from a road-speed one before opening anything.
Where the engine is at fault, the recurring items are the camshaft adjuster, the crankcase ventilation system — which blocks and pushes oil past seals in the usual way — and the ignition coils. The sandwich-floor construction makes access poor for the work, which is worth telling an owner before the estimate rather than after.
Cars fitted with this engine
2 generations, across 1 make. From the authored catalogue — an absent car means the catalogue has not reached it, not that the engine was never fitted.
Mercedes-Benz
Information, not instruction
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- The car — make, model, year and engine. The same fault behaves differently on each.
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