2005 Mazda Rx-8 — MOT failures & pass rate
The 2005 Mazda Rx-8 passed 75.0% of its 2,782 recorded MOT tests. That is 2.9 percentage points worse than coupes & convertibles of a similar age, which fail at 22.2%. Failures cluster in emissions & environmental, suspension and lighting & signalling.
What the MOT record shows
No single area dominates — emissions & environmental (12.4%) and suspension (11.5%) 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 371 times.
Mileage is the strongest signal on the record: 16.1% of 0-30k cars fail, rising to 22.2% once past 120-150k.
Advisories point at the next bill rather than this one: brakes was flagged on 27.2% of tests without failing them.
The trend is improving — the fail rate fell from 26.0% in 2021 to 21.8% in 2025, as the worst-kept examples leave the fleet.
How it compares
Top failure categories
| # | Category | % of tests affected | Tests |
|---|---|---|---|
| 1 | Emissions & environmental | 12.4% | 346 |
| 2 | Suspension | 11.5% | 320 |
| 3 | Lighting & signalling | 9.6% | 266 |
| 4 | Brakes | 7.9% | 219 |
| 5 | Body, structure & corrosion | 4.0% | 110 |
| 6 | Tyres | 3.3% | 92 |
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 | 371 |
| 2 | Component mounting prescribed areas | 225 |
| 3 | Malfunction indicator lamp | 148 |
| 4 | Headlamp aim | 139 |
| 5 | Service brake performance | 129 |
| 6 | Position lamp | 100 |
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 | 27.2% | 757 |
| 2 | Suspension | 23.3% | 647 |
| 3 | Tyres | 18.0% | 502 |
| 4 | Lighting & signalling | 11.7% | 324 |
| 5 | Emissions & environmental | 10.9% | 304 |
| 6 | Body, structure & corrosion | 10.9% | 303 |
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 | 174 | 16.1% |
| 30-60k | 1,001 | 23.6% |
| 60-90k | 1,197 | 26.7% |
| 90-120k | 340 | 27.4% |
| 120-150k | 45 | 22.2% |
Failure rate by age
Trend over time
| Dataset year | Tests | Fail rate |
|---|---|---|
| 2021 | 807 | 26.0% |
| 2022 | 637 | 24.2% |
| 2023 | 515 | 25.6% |
| 2024 | 456 | 26.5% |
| 2025 | 367 | 21.8% |
What to check before buying a 2005 Rx-8
On a 2005 Rx-8, emissions & environmental is what the MOT record says goes wrong most — it appeared in 12.4% of tests. Check these areas before you commit.
- Emissions & environmental (12.4% of tests): More common on older diesels (DPF/EGR) — can be expensive; check for warning lights and smoke. Typical repair: £100–£600.
- Suspension (11.5% 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 (9.6% 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 2005 Mazda Rx-8s pass their MOT?
75.0% of the 2,782 2005 Mazda Rx-8 MOT tests in this dataset passed — a 25.1% fail rate.
What is the most common MOT failure on a 2005 Mazda Rx-8?
Emissions & environmental, recorded in 12.4% of tests, followed by suspension (11.5%).
Does the 2005 Rx-8 get worse with mileage?
Its MOT fail rate rises from 16.1% in the 0-30k band to 22.2% in the 120-150k band.
Methodology & source. Based on 2,782 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.