Diesel BMW 120: MOT pass rate

76.2% of diesel BMW 120s pass the MOT first time, measured across 34,275 DVSA tests on that fuel type alone. Average mileage at test was 105,582.

Diesel against the other BMW 120 versions

Fuel Pass rate Tests
Diesel 76.2% 34,275
Petrol 80.4% 7,440
All BMW 12077%41,718

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 120 specifically, petrol is the strongest at 80.4%, and this diesel version sits 0.8 points below the 77% 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 BMW 120 had covered 105,582 miles at test, against 73,234 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 120 page separate age from fuel if you want to isolate one.

Other BMW 120 fuel types

All BMW 120 MOT data · Every model