Diesel Vauxhall Signum: MOT pass rate

62.2% of diesel Vauxhall Signums pass the MOT first time, measured across 704 DVSA tests on that fuel type alone. Average mileage at test was 133,312.

Diesel against the other Vauxhall Signum 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 Vauxhall Signum specifically, petrol is the strongest at 62.5%, and this diesel version sits 0.1 points below the 62.3% 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 Vauxhall Signum had covered 133,312 miles at test, against 104,906 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 Vauxhall Signum page separate age from fuel if you want to isolate one.

Most common MOT failures on a diesel Vauxhall Signum

1. Brake pipe damaged or excessively corroded, 6.9% of tests (6.47x the national rate for this defect)
2. A transmission shaft constant velocity joint boot missing or no longer prevents the ingress of dirt etc, 6.8% of tests (4.42x the national rate for this defect)
3. The aim of a headlamp is not within limits laid down in the requirements, 8.7% of tests (3.72x the national rate for this defect)
4. A spring or spring component fractured or seriously weakened, 8.3% of tests (3.65x the national rate for this defect)
5. Parking brake efficiency below minimum requirement, 4.2% of tests (3.25x the national rate for this defect)
6. Exhaust system leaking or insecure, 3.1% of tests (3.06x the national rate for this defect)
7. A suspension pin, bush or joint excessively worn, 15% of tests (2.97x the national rate for this defect)
8. Significant brake effort recorded with no brake applied indicating a binding brake, 2.5% of tests (2.45x the national rate for this defect)
9. Wiper blade missing or obviously not clearing the windscreen, 3.4% of tests (1.78x the national rate for this defect)
10. A tyre seriously damaged, 4.9% of tests (1.77x the national rate for this defect)

From 709 DVSA-tracked diesel Vauxhall Signum tests, 2024, split out from the Vauxhall Signum's other fuel types. DVSA testers marked 4.1% 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 Vauxhall Signum

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

1. Exhaust system leaking or insecure, 16.6% of tests (5.85x the national rate for this defect), also fails
2. 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, 7.6% of tests (5.02x the national rate for this defect)
3. A brake hose ferrule excessively corroded, 6.2% of tests (4.87x the national rate for this defect)
4. Product on the lens or light source which obviously reduces light intensity or changes emitted colour to other than white or yellow, 4.8% of tests (4.33x the national rate for this defect)
5. Brake pipe damaged or excessively corroded, 24.4% of tests (3.94x the national rate for this defect), also fails
6. A suspension component excessively damaged or corroded, 18.8% of tests (3.63x the national rate for this defect)
7. A spring or spring component fractured or seriously weakened, 16.5% of tests (3.49x the national rate for this defect), also fails
8. Number plate inscription missing or illegible, 6.8% of tests (2.55x the national rate for this defect)
9. Fluid leaking excessively and likely to harm the environment or to pose a safety risk to other road users, 12.1% of tests (2.18x the national rate for this defect)
10. A suspension pin, bush or joint excessively worn, 27.9% of tests (2.09x the national rate for this defect), also fails

From 709 DVSA-tracked diesel Vauxhall Signum tests, 2024.

Other Vauxhall Signum fuel types

• Petrol Vauxhall Signum - 62.5%

All Vauxhall Signum MOT data · Every model