1987 Ford Sierra — MOT failures & pass rate
1,913 MOT tests on the 1987 Ford Sierra are in this dataset, and 91.6% of them passed. Large family cars of a similar age fail 10.8% of the time, so this is 2.3pp better than the group it competes with. Failures cluster in lighting & signalling, emissions & environmental and suspension.
What the MOT record shows
No single area dominates — lighting & signalling (4.7%) and emissions & environmental (2.9%) are close, so failures are spread across several systems rather than one weak point.
At component level the recurring items are non catalyst emissions, stop lamp and component mounting prescribed areas — non catalyst emissions alone was recorded 51 times.
Mileage matters less than usual here: the 1987 Sierra fails 9.0% of the time in the 0-30k band and 8.7% at 90-120k, a spread of only 0.3 points.
The trend is improving — the fail rate fell from 10.8% in 2021 to 6.8% in 2025, as the worst-kept examples leave the fleet.
How it compares
Top failure categories
| # | Category | % of tests affected | Tests |
|---|---|---|---|
| 1 | Lighting & signalling | 4.7% | 89 |
| 2 | Emissions & environmental | 2.9% | 56 |
| 3 | Suspension | 2.7% | 52 |
| 4 | Brakes | 2.6% | 50 |
| 5 | Body, structure & corrosion | 2.1% | 41 |
| 6 | Visibility | 1.3% | 24 |
Most common specific failures
The exact components most often recorded as failures — more specific than the categories above.
| # | Failure item | Times recorded |
|---|---|---|
| 1 | Non catalyst emissions | 51 |
| 2 | Stop lamp | 26 |
| 3 | Component mounting prescribed areas | 24 |
| 4 | Headlamp aim | 22 |
| 5 | Headlamp | 22 |
| 6 | Service brake performance | 19 |
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 | 6.2% | 118 |
| 2 | Brakes | 5.1% | 97 |
| 3 | Emissions & environmental | 5.1% | 97 |
| 4 | Tyres | 4.8% | 91 |
| 5 | Body, structure & corrosion | 3.2% | 62 |
| 6 | Other defects | 3.1% | 60 |
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 | 478 | 9.0% |
| 30-60k | 565 | 7.4% |
| 60-90k | 623 | 8.8% |
| 90-120k | 241 | 8.7% |
Trend over time
| Dataset year | Tests | Fail rate |
|---|---|---|
| 2021 | 370 | 10.8% |
| 2022 | 398 | 8.8% |
| 2023 | 380 | 8.4% |
| 2024 | 395 | 7.3% |
| 2025 | 370 | 6.8% |
What to check before buying a 1987 Sierra
The failure pattern for this year is specific enough to inspect against: lighting & signalling accounted for 4.7% of tests. Start there.
- Lighting & signalling (4.7% of tests): Often a cheap bulb, but persistent issues can mean wiring or corrosion in the units. Typical repair: £10–£150.
- Emissions & environmental (2.9% of tests): More common on older diesels (DPF/EGR) — can be expensive; check for warning lights and smoke. Typical repair: £100–£600.
- Suspension (2.7% of tests): Worn drop links, bushes, springs or shocks — listen for knocks over bumps and check for uneven tyre wear. Typical repair: £150–£450 per corner.
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 1987 Ford Sierras pass their MOT?
91.6% of the 1,913 1987 Ford Sierra MOT tests in this dataset passed — a 8.4% fail rate.
What is the most common MOT failure on a 1987 Ford Sierra?
Lighting & signalling, recorded in 4.7% of tests, followed by emissions & environmental (2.9%).
Does the 1987 Sierra get worse with mileage?
Its MOT fail rate rises from 9.0% in the 0-30k band to 8.7% in the 90-120k band.
Methodology & source. Based on 1,913 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.