Porsche 911 vs Porsche 918: reliability comparison
MOT pass rates, common faults and mileage compared from real UK MOT data.
Porsche 911
85%
MOT pass rate · 74,656 vehicles
Porsche 918
88%
MOT pass rate · 8 vehicles
Verdict: On MOT pass rate the Porsche 911 (85%) and Porsche 918 (88%) are very close — weigh the individual measures below, and remember condition depends on age, mileage and upkeep.
Head to head
| Measure | Porsche 911 | Porsche 918 |
|---|---|---|
| MOT pass rate | 85% | 88% ✓ |
| MOT failure rate | 15% | 12% ✓ |
| Faults & advisories per test | 1.1 | 0.3 ✓ |
| Dangerous-fault share | 1% | 0% ✓ |
| Average mileage | 70,982 mi | 6,299 mi |
| Sample size (vehicles) | 74,656 | 8 |
Most common faults
Porsche 911
- 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)
- Under-trays fitted obscuring some underside components
- 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)
- Oil leak, but not excessive (8.4.1 (a) (i))
Porsche 918
- Front Headlamp aim projected beam image is obviously incorrect set to left hand drive (4.1.2 (c))
- Nearside Front N/S Headlight beam flat lined.
- Offside Front O/S Headlight beam flat lined.
- Under trays fitted front to rear.
- Front Registration plate missing (0.1 (a))
Reliability FAQ
On MOT pass rate the Porsche 911 (85%) and Porsche 918 (88%) are very close — weigh the individual measures below, and remember condition depends on age, mileage and upkeep.
Full Porsche 911 report Full Porsche 918 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.