Used Mercedes-Benz B-Class Air Flow Meter

Yes, petrol variants of the B-Class use a mass air flow (MAF) sensor as part of their engine management system, so the part does exist on this model. Diesel variants of the B-Class generally do not use a conventional air flow meter in the same way, relying instead on different intake sensors, so if you have a diesel B-Class you are unlikely to need this part. Check your fuel type and engine code before searching.

The W245 and W246 are completely different generations with different engine families, so an air flow meter from a 2005–2011 car is very unlikely to be a direct fit on a 2012–2018 car. The engine code is the critical detail here — even if both cars carry a similar badge like B180 or B200, the underlying engines changed between generations. Confirm the engine codes on both vehicles with your breaker before ordering.

The W246 B-Class ran from 2012 to 2018 and received a facelift around 2015, after which some engine and ancillary specifications changed. If the engine code on both cars is identical, there is a reasonable chance the MAF sensor is compatible, but ancillary mounting or connector changes introduced at the facelift cannot be confirmed without checking your registration against the specific part. Ask your breaker to verify against both registration numbers to be sure.

No, trim level does not affect air flow meter fitment on the B-Class — SE, Sport, and AMG Line are cosmetic and equipment packages that do not change the engine hardware. What matters is your engine code, fuel type, and model year, not the badge on the tailgate. Your breaker will only need your registration or engine code to identify the correct part.

The most useful single piece of information is your engine code, which is printed on your V5C or can be retrieved via a VIN check — it will look something like M270 or M274 for common petrol variants. You should also have your fuel type, year of registration, and mileage to hand, as breakers may want to match a like-for-like unit. Be aware that air flow meters can sometimes require coding or pairing to the vehicle's ECU, so confirm with your breaker whether the unit you are buying needs any additional setup before fitting.

Engine size alone is not a reliable guide — a B180 and a B200 may share an engine code in some model years, meaning the MAF sensor could be the same unit, but this is not always the case across different years or after engine family changes. The engine code is a far more reliable matching point than the displacement badge, because Mercedes has used the same physical engine in different states of tune under different model names. Always supply your engine code to the breaker rather than relying on the B180 or B200 designation.