Diesel BMW 4 Series: MOT pass rate
80.9% of diesel BMW 4 Series pass the MOT first time, measured across 655 DVSA tests on that fuel type alone. Average mileage at test was 98,673.
Diesel against the other BMW 4 Series versions
| Fuel | Pass rate | Tests |
|---|---|---|
| Diesel | 80.9% | 655 |
| Petrol | 86.7% | 578 |
| All BMW 4 Series | 83.6% | 1,233 |
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 BMW 4 Series specifically, petrol is the strongest at 86.7%, and this diesel version sits 2.7 points below the 83.6% model average.
What it means if you are buying one
The diesel BMW 4 Series fails more often than the model average, so budget for the items that catch this fuel type and treat a fresh MOT as worth paying for. Check the exact car, decode the VIN and check the mileage before you bid.
Mileage is part of the answer
The average diesel BMW 4 Series had covered 98,673 miles at test, against 60,744 for the petrol. That is above average and into the range where cambelts and water pumps are due if they have not already been done, so ask for the service history rather than take the mileage on trust.
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 BMW 4 Series page separate age from fuel if you want to isolate one.
Other BMW 4 Series fuel types
- Petrol BMW 4 Series - 86.7%