1985 Porsche 924 — MOT failures & pass rate
Across 401 MOT tests analysed for the 1985 Porsche 924, the most common recorded failure areas were lighting & signalling, visibility and brakes. Its pass rate of 78.3% was below the average for cars of a similar age (80.9%).
How it compares
Top failure categories
| # | Category | % of tests affected | Tests |
|---|---|---|---|
| 1 | Lighting & signalling | 12.2% | 49 |
| 2 | Visibility | 9.7% | 39 |
| 3 | Brakes | 9.7% | 39 |
| 4 | Body, structure & corrosion | 7.0% | 28 |
| 5 | Suspension | 4.7% | 19 |
| 6 | Emissions & environmental | 4.7% | 19 |
Most common specific failures
The exact components most often recorded as failures — more specific than the categories above.
| # | Failure item | Times recorded |
|---|---|---|
| 1 | Washers | 30 |
| 2 | Service brake performance | 23 |
| 3 | Headlamp aim | 22 |
| 4 | Rigid brake pipes | 22 |
| 5 | Wipers | 16 |
| 6 | Non catalyst emissions | 14 |
Top advisory categories
Advisories aren't failures, but they flag work likely needed soon — useful when budgeting.
| # | Category | % of tests with advisory | Tests |
|---|---|---|---|
| 1 | Brakes | 26.4% | 106 |
| 2 | Suspension | 19.7% | 79 |
| 3 | Body, structure & corrosion | 9.5% | 38 |
| 4 | Other defects | 9.5% | 38 |
| 5 | Emissions & environmental | 8.0% | 32 |
| 6 | Lighting & signalling | 6.7% | 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 | 134 | 25.4% |
| 30-60k | 116 | 20.7% |
| 60-90k | 117 | 21.4% |
| 90-120k | 34 | 11.8% |
Trend over time
| Dataset year | Tests | Fail rate |
|---|---|---|
| 2021 | 98 | 22.4% |
| 2022 | 89 | 16.9% |
| 2023 | 81 | 25.9% |
| 2024 | 75 | 24.0% |
| 2025 | 58 | 19.0% |
What to check before buying a 1985 924
Before buying a 1985 Porsche 924, focus on the areas it most often fails on. Lighting & signalling accounted for 12.2% of tests for this year.
- Lighting & signalling (12.2% of tests): Often a cheap bulb, but persistent issues can mean wiring or corrosion in the units. Typical repair: £10–£150.
- Visibility (9.7% of tests): Wipers, washers, mirrors and screen damage — usually inexpensive, but check for chips in the driver's line of sight. Typical repair: £15–£150.
- Brakes (9.7% of tests): Pads/discs are routine wear; binding, imbalance or corroded pipes are more serious — test for pulling under braking. Typical repair: £100–£350 per axle.
Repair costs are rough UK ballpark ranges to set expectations, not quotes — actual prices vary widely by car, parts and garage.
Frequently asked questions
How many 1985 Porsche 924s pass their MOT?
78.3% of the 401 1985 Porsche 924 MOT tests in this dataset passed — a 21.7% fail rate.
What is the most common MOT failure on a 1985 Porsche 924?
Lighting & signalling, recorded in 12.2% of tests, followed by visibility (9.7%).
Does the 1985 924 get worse with mileage?
Its MOT fail rate rises from 25.4% in the 0-30k band to 11.8% in the 90-120k band.
Methodology & source. Based on 401 MOT tests. Dataset: DVSA MOT testing data (2021,2022,2023,2024,2025). Data last updated 2026-07-01. Figures reflect MOT-testable defects only — read the methodology for how these are calculated and what they don't measure.