Diesel Subaru Legacy: MOT pass rate

64.1% of diesel Subaru Legacies pass the MOT first time, measured across 761 DVSA tests on that fuel type alone. Average mileage at test was 114,746.

Diesel against the other Subaru Legacy 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 Subaru Legacy specifically, petrol is the strongest at 70.3%, and this diesel version sits 5.3 points below the 69.4% model average.

What it means if you are buying one

The diesel Subaru Legacy 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. 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 Subaru Legacy had covered 114,746 miles at test, against 112,035 for the petrol. That is high mileage, so timing belts, clutches, suspension bushes and corrosion are the items worth budgeting for rather than the MOT itself.

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 Subaru Legacy page separate age from fuel if you want to isolate one.

Most common MOT failures on a diesel Subaru Legacy

1. ESC MIL indicates a system malfunction, 4.7% of tests (23.21x the national rate for this defect)
2. Headlamp levelling device inoperative, 2.6% of tests (19.18x the national rate for this defect)
3. A suspension component excessively damaged or corroded, 2.7% of tests (7.84x the national rate for this defect)
4. A lamp missing, inoperative or in the case of a multiple light source more than 1/2 not functioning, 11.9% of tests (5.33x the national rate for this defect)
5. Engine MIL illuminated indicating a malfunction, 6% of tests (4.69x the national rate for this defect)
6. A suspension pin, bush or joint excessively worn, 18.3% of tests (3.63x the national rate for this defect)
7. A rear registration plate lamp or light source missing or inoperative in the case of a single lamp or all lamps, 2.7% of tests (3.07x the national rate for this defect)
8. Brake pipe damaged or excessively corroded, 2.6% of tests (2.44x the national rate for this defect)
9. A tyre seriously damaged, 6.6% of tests (2.38x 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, 3.1% of tests (2.3x the national rate for this defect)

From 767 DVSA-tracked diesel Subaru Legacy tests, 2024, split out from the Subaru Legacy's other fuel types. DVSA testers marked 4.85% 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 Subaru Legacy

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

1. A suspension pin, bush or joint excessively worn, 62.5% of tests (4.67x the national rate for this defect), also fails
2. A suspension component excessively damaged or corroded, 22.3% of tests (4.31x the national rate for this defect), also fails
3. Product on the lens or light source which obviously reduces light intensity or changes emitted colour to other than white or yellow, 3.7% of tests (3.3x the national rate for this defect)
4. Vehicle structure corroded to the extent that the rigidity of the assembly is seriously reduced, 3.9% of tests (3.14x the national rate for this defect)
5. Brake pipe damaged or excessively corroded, 19% of tests (3.07x the national rate for this defect), also fails
6. The strength or continuity of the load bearing structure within 30cm of any sub-frame, spring or suspension component mounting (a 'prescribed area') is significantly reduced or inadequately repaired, 3.3% of tests (2.15x the national rate for this defect)
7. Brake disc or drum excessively weakened, insecure or fractured, 23.6% of tests (1.93x the national rate for this defect)
8. A spring or spring component fractured or seriously weakened, 7.8% of tests (1.66x the national rate for this defect)
9. Number plate inscription missing or illegible, 3.8% of tests (1.43x the national rate for this defect)
10. Exhaust system leaking or insecure, 4% of tests (1.42x the national rate for this defect)

From 767 DVSA-tracked diesel Subaru Legacy tests, 2024.

Other Subaru Legacy fuel types

• Petrol Subaru Legacy - 70.3%

All Subaru Legacy MOT data · Every model