2003 BMW Z3 — MOT failures & pass rate
557 MOT tests on the 2003 BMW Z3 are in this dataset, and 81.7% of them passed. Against coupes & convertibles of a similar age (22.6% fail rate), the 2003 Z3 comes out 4.2pp better. Failures cluster in brakes, lighting & signalling and suspension.
What the MOT record shows
No single area dominates — brakes (8.8%) and lighting & signalling (8.1%) are close, so failures are spread across several systems rather than one weak point.
At component level the recurring items are washers, rigid brake pipes and headlamp aim — washers alone was recorded 23 times.
Condition tracks the odometer closely. Failures run at 9.5% in the 0-30k band and 21.6% in the 120-150k band, a 12.1-point spread — more than double.
Brakes is the most common advisory, noted on 31.2% of tests — work that passed today but is likely due soon.
The trend is improving — the fail rate fell from 20.1% in 2021 to 15.0% in 2025, as the worst-kept examples leave the fleet.
How it compares
Top failure categories
| # | Category | % of tests affected | Tests |
|---|---|---|---|
| 1 | Brakes | 8.8% | 49 |
| 2 | Lighting & signalling | 8.1% | 45 |
| 3 | Suspension | 5.4% | 30 |
| 4 | Visibility | 5.2% | 29 |
| 5 | Tyres | 2.5% | 14 |
| 6 | Emissions & environmental | 1.8% | 10 |
Most common specific failures
The exact components most often recorded as failures — more specific than the categories above.
| # | Failure item | Times recorded |
|---|---|---|
| 1 | Washers | 23 |
| 2 | Rigid brake pipes | 21 |
| 3 | Headlamp aim | 18 |
| 4 | Service brake performance | 16 |
| 5 | Position lamp | 14 |
| 6 | Ball joint | 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 | 31.2% | 174 |
| 2 | Suspension | 21.4% | 119 |
| 3 | Tyres | 19.0% | 106 |
| 4 | Lighting & signalling | 11.5% | 64 |
| 5 | Emissions & environmental | 10.2% | 57 |
| 6 | Other defects | 8.1% | 45 |
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 | 42 | 9.5% |
| 30-60k | 198 | 19.7% |
| 60-90k | 153 | 14.4% |
| 90-120k | 110 | 21.8% |
| 120-150k | 37 | 21.6% |
Failure rate by age
Trend over time
| Dataset year | Tests | Fail rate |
|---|---|---|
| 2021 | 154 | 20.1% |
| 2022 | 99 | 16.2% |
| 2023 | 106 | 17.9% |
| 2024 | 105 | 20.9% |
| 2025 | 93 | 15.0% |
What to check before buying a 2003 Z3
The failure pattern for this year is specific enough to inspect against: brakes accounted for 8.8% of tests. Start there.
- Brakes (8.8% 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.
- Lighting & signalling (8.1% of tests): Often a cheap bulb, but persistent issues can mean wiring or corrosion in the units. Typical repair: £10–£150.
- Suspension (5.4% 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 2003 BMW Z3s pass their MOT?
81.7% of the 557 2003 BMW Z3 MOT tests in this dataset passed — a 18.3% fail rate.
What is the most common MOT failure on a 2003 BMW Z3?
Brakes, recorded in 8.8% of tests, followed by lighting & signalling (8.1%).
Does the 2003 Z3 get worse with mileage?
Its MOT fail rate rises from 9.5% in the 0-30k band to 21.6% in the 120-150k band.
Methodology & source. Based on 557 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.