Known faults for the Mercedes-Benz Clase X.

Engine / equipment

OM654 2.0 and OM656 3.0 diesel (C, E, S, GLC, GLE, GLS, G-Class from 2016)

Period mentioned

2016–2026

Symptoms

AdBlue or emissions warnings with a start countdown; particulate filter warning; power loss or rough idle from a dirty EGR.

Possible cause described

These are robust engines; faults concentrate in the emissions system. The AdBlue system (injector, NOx sensors and SCR catalyst) sometimes fails, especially in the cold, and the particulate filter and EGR foul if the car mostly does short trips.

Check for the garage

Read AdBlue and NOx sensor codes with Xentry, check the particulate filter regeneration history and how the car is used (short trips).

Cost cited in the source

AdBlue system: approx. €500–1,200; particulate filter: €1,000–2,000A rough figure from the original database, not an up-to-date quote.

Mileage cited in the database: from 100,000 km. This is not a maintenance interval and does not predict a failure.

Sources from the original database

Engine / equipment

OM642 3.0 V6 CDI/BlueTEC (280/300/320/350 CDI, ML, GL, R, Sprinter)

Period mentioned

2005 onwards

Symptoms

Oil pooling in the engine's V, burning oil smell, drips under the engine; or a hiss or chirp next to an injector with an exhaust smell.

Possible cause described

The oil cooler seals (in the engine's V) degrade. Separately, injector washers leak combustion gas and carbon builds up around the injector.

Check for the garage

Visual inspection of the engine's V and the base of the injectors.

Cost cited in the source

Oil cooler seals: labour-heavy, approx. €800–1,800 (estimate)A rough figure from the original database, not an up-to-date quote.

Sources from the original database