Used Mercedes-Benz X-Class Oxygen Sensor

No — the Mercedes-Benz X-Class (2017–2020) was sold exclusively with diesel engines (2.3-litre and 3.0-litre units), and diesel engines do not use oxygen sensors in the way petrol engines do. Diesels use NOx sensors, exhaust gas temperature sensors, and lambda sensors specific to diesel aftertreatment systems rather than the conventional upstream/downstream oxygen sensors found on petrol cars. If you are trying to diagnose an exhaust or emissions fault on your X-Class, you are most likely looking for a NOx sensor, an exhaust gas temperature (EGT) sensor, or a diesel-specific lambda sensor — confirm exactly which sensor your fault code points to with a breaker or a Mercedes specialist before ordering.

Because the X-Class is diesel-only, the sensor triggering your fault is almost certainly a NOx sensor, an EGT (exhaust gas temperature) sensor, or a diesel lambda/wideband sensor used by the SCR (AdBlue) system rather than a conventional oxygen sensor. When contacting a breaker, quote your registration and engine code (for example the 2.3 OM626 or the 3.0 OM642) so they can identify the correct sensor position and part number. Searching for 'oxygen sensor' on a diesel X-Class is unlikely to return the right part, so using the correct sensor name will save time.

Yes, it matters significantly — the 2.3-litre four-cylinder (OM626-based) and the 3.0-litre V6 (OM642) have different exhaust systems, different sensor counts, and different sensor positions, so sensors from one engine will not simply cross over to the other. The 3.0 V6 models also tend to have more complex aftertreatment hardware, which affects which sensors are present and where. Always give the breaker your engine code alongside your registration to make sure you are quoted the right part.

No — trim level (Pure, Progressive, Power, or the limited-run AMG Line) does not affect the exhaust sensor setup; what determines the sensors fitted is the engine code and the emissions standard the vehicle was built to. All X-Class models were Euro 6, but there can be software and hardware differences between earlier and later build dates, so confirm the exact sensor part number with the breaker against your registration rather than relying on trim alone. Cosmetically the trim levels differ in wheels, interior finish, and bodywork details, but none of that influences the exhaust system sensors.

The X-Class ran from 2017 to 2020 with no formal facelift, but minor running changes to emissions hardware and software calibration can occur across a production run even within a single generation. This means a sensor from a 2017-build car and one from a 2019-build car may differ in part number even if they look identical. Confirm the sensor part number with the breaker against your specific registration to avoid buying a visually similar but incompatible unit.