Porsche 911 Carrera 4S MOT pass rate & common failures
Across 23 model years and 1,000 tests, the Porsche 911 Carrera 4S passes its MOT 92.0% of the time. All cars of a similar age fail 14.8% of the time, so this is 6.8pp better than the group it competes with. Its most common failure areas are tyres, lighting & signalling and body, structure & corrosion.
What the MOT record shows
No single area dominates — tyres (4.2%) and lighting & signalling (2.2%) are close, so failures are spread across several systems rather than one weak point.
At component level the recurring items are headlamp aim, joints and tread depth — headlamp aim alone was recorded 17 times.
Condition tracks the odometer closely. Failures run at 5.1% in the 0-30k band and 12.1% in the 90-120k band, a 7.0-point spread — more than double.
Tyres is the most common advisory, noted on 13.1% of tests — work that passed today but is likely due soon.
The trend is improving — the fail rate fell from 13.0% in 2021 to 7.6% in 2025, as the worst-kept examples leave the fleet.
How it compares
By model year
Every 911 Carrera 4S model year with a usable sample. Years with their own detailed report are linked.
| Year | Tests | Pass rate | Fail rate | Most common failure |
|---|---|---|---|---|
| 2002 | 42 | 83.3% | 16.7% | Lighting & signalling |
| 2003 | 43 | 86.1% | 14.0% | Body, structure & corrosion |
| 2004 | 46 | 82.6% | 17.4% | Body, structure & corrosion |
| 2009 | 62 | 91.9% | 8.1% | Tyres |
| 2013 | 56 | 87.5% | 12.5% | Tyres |
| 2020 | 243 | 94.7% | 5.3% | Tyres |
| 2021 | 322 | 96.0% | 4.0% | Tyres |
| 2022 | 61 | 91.8% | 8.2% | Tyres |
Most common failures (all years)
| # | Category | % of tests affected | Tests |
|---|---|---|---|
| 1 | Tyres | 4.2% | 42 |
| 2 | Lighting & signalling | 2.2% | 22 |
| 3 | Body, structure & corrosion | 1.8% | 18 |
| 4 | Visibility | 0.9% | 9 |
| 5 | Suspension | 0.9% | 9 |
| 6 | Emissions & environmental | 0.7% | 7 |
| 7 | Brakes | 0.6% | 6 |
| 8 | Other defects | 0.3% | 3 |
Most common specific failures
The exact components most often recorded as failures — more specific than the categories above.
| # | Failure item | Times recorded |
|---|---|---|
| 1 | Headlamp aim | 17 |
| 2 | Joints | 16 |
| 3 | Tread depth | 10 |
| 4 | Catalyst emissions | 9 |
| 5 | Rigid brake pipes | 8 |
| 6 | Registration plates | 6 |
| 7 | Washers | 5 |
| 8 | Wipers | 4 |
Top advisory categories
Advisories aren't failures, but they flag work likely needed soon — useful when budgeting.
| # | Category | % of tests with advisory | Tests |
|---|---|---|---|
| 1 | Tyres | 13.1% | 131 |
| 2 | Brakes | 6.7% | 67 |
| 3 | Other defects | 5.0% | 50 |
| 4 | Suspension | 3.7% | 37 |
| 5 | Lighting & signalling | 3.0% | 30 |
| 6 | Visibility | 2.7% | 27 |
Failure rate by mileage
Higher-mileage cars tend to fail more — often the most useful guide to real condition.
| Mileage band | Tests | Fail rate |
|---|---|---|
| 0-30k | 643 | 5.1% |
| 30-60k | 144 | 9.7% |
| 60-90k | 180 | 16.1% |
| 90-120k | 33 | 12.1% |
Failure rate by age
Trend over time
| Dataset year | Tests | Fail rate |
|---|---|---|
| 2021 | 69 | 13.0% |
| 2022 | 62 | 4.8% |
| 2023 | 142 | 8.5% |
| 2024 | 334 | 7.8% |
| 2025 | 393 | 7.6% |
What to check before buying a Porsche 911 Carrera 4S
- Tyres (4.2% of tests): Usually a quick, known-cost fix, but check tread, age and uneven wear (which can hint at alignment or suspension issues). Typical repair: £50–£120 per tyre.
- Lighting & signalling (2.2% of tests): Often a cheap bulb, but persistent issues can mean wiring or corrosion in the units. Typical repair: £10–£150.
- Body, structure & corrosion (1.8% of tests): The one to take seriously on older cars — corrosion to structural areas can be costly and is an MOT failure. Typical repair: £200–£1,500+.
Repair costs are rough UK ballpark ranges to set expectations, not quotes — actual prices vary widely by car, parts and garage.
Frequently asked questions
What is the MOT pass rate for the Porsche 911 Carrera 4S?
92.0% of the 1,000 Porsche 911 Carrera 4S MOT tests in this dataset passed, an 8.0% fail rate, across model years 2001–2023.
What does the Porsche 911 Carrera 4S most often fail its MOT on?
Tyres, recorded in 4.2% of tests, then lighting & signalling (2.2%).
How much does mileage affect 911 Carrera 4S MOT results?
Fail rates run at 5.1% for cars in the 0-30k band and 12.1% for 90-120k, a 7.0-point difference.
Methodology & source. Based on 1,000 MOT tests. Dataset: DVSA MOT testing data (2021,2022,2023,2024,2025). Data last updated 2026-07-27. Figures reflect MOT-testable defects only — read the methodology for how these are calculated and what they don't measure.