1998 Caterham Seven S3 — MOT failures & pass rate
The 1998 Caterham Seven S3 passed 88.6% of its 449 recorded MOT tests. That is 14.2 percentage points better than all cars of a similar age, which fail at 25.6%. Failures cluster in lighting & signalling, emissions & environmental and brakes.
What the MOT record shows
One area stands out: lighting & signalling, recorded in 6.7% of tests against 3.6% for the next-worst category.
At component level the recurring items are steering rack, non catalyst emissions and headlamp aim — steering rack alone was recorded 10 times.
Suspension is the most common advisory, noted on 9.8% of tests — work that passed today but is likely due soon.
The trend is improving — the fail rate fell from 16.5% in 2021 to 13.3% in 2025, as the worst-kept examples leave the fleet.
How it compares
Top failure categories
| # | Category | % of tests affected | Tests |
|---|---|---|---|
| 1 | Lighting & signalling | 6.7% | 30 |
| 2 | Emissions & environmental | 3.6% | 16 |
| 3 | Brakes | 2.7% | 12 |
| 4 | Suspension | 2.2% | 10 |
| 5 | Steering | 2.0% | 9 |
| 6 | Visibility | 1.6% | 7 |
Most common specific failures
The exact components most often recorded as failures — more specific than the categories above.
| # | Failure item | Times recorded |
|---|---|---|
| 1 | Steering rack | 10 |
| 2 | Non catalyst emissions | 10 |
| 3 | Headlamp aim | 9 |
| 4 | Catalyst emissions | 9 |
| 5 | Stop lamp | 7 |
| 6 | Rear fog lamp | 7 |
Top advisory categories
Advisories aren't failures, but they flag work likely needed soon — useful when budgeting.
| # | Category | % of tests with advisory | Tests |
|---|---|---|---|
| 1 | Suspension | 9.8% | 44 |
| 2 | Brakes | 7.1% | 32 |
| 3 | Visibility | 4.2% | 19 |
| 4 | Emissions & environmental | 3.3% | 15 |
| 5 | Tyres | 2.7% | 12 |
| 6 | Steering | 2.7% | 12 |
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 | 349 | 10.9% |
| 30-60k | 79 | 15.2% |
Failure rate by age
Trend over time
| Dataset year | Tests | Fail rate |
|---|---|---|
| 2021 | 97 | 16.5% |
| 2022 | 92 | 12.0% |
| 2023 | 99 | 10.1% |
| 2024 | 78 | 3.9% |
| 2025 | 83 | 13.3% |
What to check before buying a 1998 Seven S3
The failure pattern for this year is specific enough to inspect against: lighting & signalling accounted for 6.7% of tests. Start there.
- Lighting & signalling (6.7% of tests): Often a cheap bulb, but persistent issues can mean wiring or corrosion in the units. Typical repair: £10–£150.
- Emissions & environmental (3.6% of tests): More common on older diesels (DPF/EGR) — can be expensive; check for warning lights and smoke. Typical repair: £100–£600.
- Brakes (2.7% 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 1998 Caterham Seven S3s pass their MOT?
88.6% of the 449 1998 Caterham Seven S3 MOT tests in this dataset passed — a 11.4% fail rate.
What is the most common MOT failure on a 1998 Caterham Seven S3?
Lighting & signalling, recorded in 6.7% of tests, followed by emissions & environmental (3.6%).
Does the 1998 Seven S3 get worse with mileage?
Its MOT fail rate rises from 10.9% in the 0-30k band to 15.2% in the 30-60k band.
Methodology & source. Based on 449 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.