Diesel Fiat 500 L: MOT pass rate

66.1% of diesel Fiat 500 Ls pass the MOT first time, measured across 2,624 DVSA tests on that fuel type alone. Average mileage at test was 80,392.

Diesel against the other Fiat 500 L versions

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 Fiat 500 L specifically, petrol is the strongest at 67.9%, and this diesel version sits 0.6 points below the 66.7% 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. Buying a damaged one? run it through the analyzer, check the exact car, decode the VIN and check the mileage before you bid.

Mileage is part of the answer

The average diesel Fiat 500 L had covered 80,392 miles at test, against 69,391 for the petrol. That is above average, the point where suspension bushes, drop links and exhaust corrosion start showing up as advisories before they become failures.

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 Fiat 500 L page separate age from fuel if you want to isolate one.

Most common MOT failures on a diesel Fiat 500 L

1. A suspension pin, bush or joint likely to become detached, 1.4% of tests (5.95x the national rate for this defect)
2. A spring or spring component fractured or seriously weakened, 8.2% of tests (3.6x the national rate for this defect)
3. Parking brake efficiency below minimum requirement, 4.6% of tests (3.54x the national rate for this defect)
4. Steering rack gaiter or ball joint dust cover missing or no longer prevents the ingress of dirt etc, 2.3% of tests (3.07x the national rate for this defect)
5. Brake disc or drum significantly and obviously worn, 2.2% of tests (2.74x the national rate for this defect)
6. A steering ball joint with excessive wear or free play, 2.8% of tests (2.13x the national rate for this defect)
7. a brake lining or pad worn below 1.5mm, 4.1% of tests (1.9x the national rate for this defect)
8. Engine MIL illuminated indicating a malfunction, 2.3% of tests (1.82x the national rate for this defect)
9. A suspension pin, bush or joint excessively worn, 9% of tests (1.79x the national rate for this defect)
10. Stop lamp missing, inoperative or in the case of a multiple light source more than 1/2 not functioning, 2.2% of tests (1.65x the national rate for this defect)

From 2,624 DVSA-tracked diesel Fiat 500 L tests, 2024, split out from the Fiat 500 L's other fuel types. DVSA testers marked 7.25% of these flagged defects as "dangerous", against 5.11% nationally. See which fuel type fails on the most dangerous defects nationally for how that compares across the whole fleet.

Most common MOT advisories on a diesel Fiat 500 L

Flagged but doesn't fail the car, a different list from the failures above.

1. A stub axle swivel pin and/or bush excessively worn, 1.9% of tests (2.97x the national rate for this defect)
2. Brake disc or drum significantly and obviously worn, 5.6% of tests (1.77x the national rate for this defect), also fails
3. Brake disc or drum excessively weakened, insecure or fractured, 20.3% of tests (1.66x the national rate for this defect)
4. A steering ball joint with excessive wear or free play, 2% of tests (1.49x the national rate for this defect), also fails
5. Significant brake effort recorded with no brake applied indicating a binding brake, 2.6% of tests (1.32x the national rate for this defect)
6. Tyre tread depth not in accordance with the requirements, 32.2% of tests (1.21x the national rate for this defect)
7. A suspension pin, bush or joint excessively worn, 16.2% of tests (1.21x the national rate for this defect), also fails
8. A tyre seriously damaged, 18.1% of tests (1.17x the national rate for this defect)
9. a brake lining or pad worn below 1.5mm, 10.8% of tests, also fails
10. Fluid leaking excessively and likely to harm the environment or to pose a safety risk to other road users, 5.2% of tests

From 2,624 DVSA-tracked diesel Fiat 500 L tests, 2024.

Other Fiat 500 L fuel types

• Petrol Fiat 500 L - 67.9%

All Fiat 500 L MOT data · Every model