2003 Mazda Rx-8 — MOT failures & pass rate
The 2003 Mazda Rx-8 passed 76.1% of its 682 recorded MOT tests. That is 1.3 percentage points worse than coupes & convertibles of a similar age, which fail at 22.6%. Failures cluster in emissions & environmental, suspension and lighting & signalling.
What the MOT record shows
No single area dominates — emissions & environmental (11.6%) and suspension (9.8%) are close, so failures are spread across several systems rather than one weak point.
At component level the recurring items are catalyst emissions, component mounting prescribed areas and malfunction indicator lamp — catalyst emissions alone was recorded 78 times.
Mileage is the strongest signal on the record: 12.1% of 0-30k cars fail, rising to 29.2% once past 90-120k — 2.4× the risk.
Advisories point at the next bill rather than this one: brakes was flagged on 26.3% of tests without failing them.
The trend is worsening — 25.4% of tests failed in 2021 against 28.1% in 2025, the usual pattern as a fleet ages.
How it compares
Top failure categories
| # | Category | % of tests affected | Tests |
|---|---|---|---|
| 1 | Emissions & environmental | 11.6% | 79 |
| 2 | Suspension | 9.8% | 67 |
| 3 | Lighting & signalling | 9.5% | 65 |
| 4 | Brakes | 7.2% | 49 |
| 5 | Body, structure & corrosion | 5.0% | 34 |
| 6 | Visibility | 3.8% | 26 |
Most common specific failures
The exact components most often recorded as failures — more specific than the categories above.
| # | Failure item | Times recorded |
|---|---|---|
| 1 | Catalyst emissions | 78 |
| 2 | Component mounting prescribed areas | 69 |
| 3 | Malfunction indicator lamp | 39 |
| 4 | Headlamp aim | 38 |
| 5 | Service brake performance | 36 |
| 6 | Integral vehicle structure condition | 34 |
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 | 26.3% | 179 |
| 2 | Suspension | 24.9% | 170 |
| 3 | Tyres | 23.6% | 161 |
| 4 | Body, structure & corrosion | 13.8% | 94 |
| 5 | Emissions & environmental | 12.8% | 87 |
| 6 | Lighting & signalling | 11.9% | 81 |
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 | 58 | 12.1% |
| 30-60k | 222 | 20.7% |
| 60-90k | 249 | 26.1% |
| 90-120k | 130 | 29.2% |
Failure rate by age
Trend over time
| Dataset year | Tests | Fail rate |
|---|---|---|
| 2021 | 193 | 25.4% |
| 2022 | 151 | 21.9% |
| 2023 | 137 | 24.8% |
| 2024 | 105 | 19.1% |
| 2025 | 96 | 28.1% |
What to check before buying a 2003 Rx-8
On a 2003 Rx-8, emissions & environmental is what the MOT record says goes wrong most — it appeared in 11.6% of tests. Check these areas before you commit.
- Emissions & environmental (11.6% of tests): More common on older diesels (DPF/EGR) — can be expensive; check for warning lights and smoke. Typical repair: £100–£600.
- Suspension (9.8% 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.
- Lighting & signalling (9.5% of tests): Often a cheap bulb, but persistent issues can mean wiring or corrosion in the units. Typical repair: £10–£150.
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 2003 Mazda Rx-8s pass their MOT?
76.1% of the 682 2003 Mazda Rx-8 MOT tests in this dataset passed — a 23.9% fail rate.
What is the most common MOT failure on a 2003 Mazda Rx-8?
Emissions & environmental, recorded in 11.6% of tests, followed by suspension (9.8%).
Does the 2003 Rx-8 get worse with mileage?
Its MOT fail rate rises from 12.1% in the 0-30k band to 29.2% in the 90-120k band.
Methodology & source. Based on 682 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.