Diesel Mercedes-Benz B-Class: MOT pass rate
75.1% of diesel Mercedes-Benz B-Class pass the MOT first time, measured across 43,228 DVSA tests on that fuel type alone. Average mileage at test was 78,400.
Diesel against the other Mercedes-Benz B-Class versions
| Fuel | Pass rate | Tests |
|---|---|---|
| Diesel | 75.1% | 43,228 |
| Petrol | 75.2% | 19,996 |
| Electric | 84.5% | 399 |
| All Mercedes-Benz B-Class | 75.2% | 63,625 |
Why the fuel type changes the number
Diesels carry DPFs, EGR valves and stricter smoke limits, so emissions and exhaust faults account for failures petrol cars never see.
On the Mercedes-Benz B-Class specifically, electric is the strongest at 84.5%, and this diesel version sits 0.1 points below the 75.2% model average.
What it means if you are buying one
There is little to choose between fuel types on this model, so decide on running costs and mileage rather than MOT record. Check the exact car, decode the VIN and check the mileage before you bid.
Mileage is part of the answer
The average diesel Mercedes-Benz B-Class had covered 78,400 miles at test, against 71,194 for the petrol and 45,186 for the electric. That is a shade above the middle of the range, still ordinary wear rather than a red flag, but worth checking against the service book for the car's age.
Fuel type and mileage are tangled together: diesels are usually bought by higher-mileage drivers, so some of any gap between fuels is the miles rather than the engine. The per-year figures on the Mercedes-Benz B-Class page separate age from fuel if you want to isolate one.
Other Mercedes-Benz B-Class fuel types
- Petrol Mercedes-Benz B-Class - 75.2%
- Electric Mercedes-Benz B-Class - 84.5%