Audi A6 vs Audi Tt tdi quattro: reliability comparison
MOT pass rates, common faults and mileage compared from real UK MOT data.
Audi A6
78%
MOT pass rate · 246,602 vehicles
Audi Tt tdi quattro
82%
MOT pass rate · 1 vehicles
Verdict: On MOT pass rate the Audi A6 (78%) and Audi Tt tdi quattro (82%) are very close — weigh the individual measures below, and remember condition depends on age, mileage and upkeep.
Head to head
| Measure | Audi A6 | Audi Tt tdi quattro |
|---|---|---|
| MOT pass rate | 78% | 82% ✓ |
| MOT failure rate | 22% | 18% ✓ |
| Faults & advisories per test | 1.7 ✓ | 1.9 |
| Dangerous-fault share | 2% | 0% ✓ |
| Average mileage | 136,441 mi | 151,639 mi |
| Sample size (vehicles) | 246,602 | 1 |
Most common faults
Audi A6
- Nearside Front Tyre worn close to the legal limit (4.1.E.1)
- Offside Front Tyre worn close to the legal limit (4.1.E.1)
- Nearside Front Tyre worn close to legal limit/worn on edge (5.2.3 (e))
- Offside Front Tyre worn close to legal limit/worn on edge (5.2.3 (e))
- Nearside Rear Tyre worn close to the legal limit (4.1.E.1)
- Offside Rear Tyre worn close to the legal limit (4.1.E.1)
Audi Tt tdi quattro
- engine covers & under trays fitted obscuring some components/areas
- o/s & n/s front tyres worn smooth at inner edge/shoulder
- 225/50R17
- COOLANT LOW
- Nearside Front Tyre worn close to legal limit/worn on edge JUST ABOVE THE TREAD WEAR BARS (5.2.3 (e))
- Offside Front Tyre worn close to legal limit/worn on edge GOING BALD INSIDE (5.2.3 (e))
Reliability FAQ
On MOT pass rate the Audi A6 (78%) and Audi Tt tdi quattro (82%) are very close — weigh the individual measures below, and remember condition depends on age, mileage and upkeep.
Full Audi A6 report Full Audi Tt tdi quattro report Most reliable cars
Pass rates are computed over completed (pass/fail) MOT tests. Reliability also depends on age, mileage and upkeep — see each model's page for the full picture.