2003 BMW Z4 — MOT failures & pass rate
The 2003 BMW Z4 passed 77.5% of its 16,488 recorded MOT tests. Coupes & convertibles of a similar age fail at 22.6%, so the 2003 Z4 sits squarely on the average. Failures cluster in brakes, suspension and lighting & signalling.
What the MOT record shows
No single area dominates — brakes (9.1%) and suspension (9.0%) are close, so failures are spread across several systems rather than one weak point.
At component level the recurring items are rigid brake pipes, headlamp aim and srs malfunction indicator lamp — rigid brake pipes alone was recorded 930 times.
Mileage is the strongest signal on the record: 11.4% of 0-30k cars fail, rising to 28.9% once past 150k — 2.5× the risk.
Advisories point at the next bill rather than this one: brakes was flagged on 36.9% of tests without failing them.
The trend is improving — the fail rate fell from 24.0% in 2021 to 20.8% in 2025, as the worst-kept examples leave the fleet.
How it compares
Top failure categories
| # | Category | % of tests affected | Tests |
|---|---|---|---|
| 1 | Brakes | 9.1% | 1,503 |
| 2 | Suspension | 9.0% | 1,492 |
| 3 | Lighting & signalling | 8.5% | 1,407 |
| 4 | Visibility | 5.3% | 865 |
| 5 | Tyres | 4.7% | 768 |
| 6 | Seat belts & restraints | 4.5% | 734 |
Most common specific failures
The exact components most often recorded as failures — more specific than the categories above.
| # | Failure item | Times recorded |
|---|---|---|
| 1 | Rigid brake pipes | 930 |
| 2 | Headlamp aim | 877 |
| 3 | SRS malfunction indicator lamp | 707 |
| 4 | Tread depth | 605 |
| 5 | Ball joint | 544 |
| 6 | Wipers | 539 |
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 | 36.9% | 6,087 |
| 2 | Suspension | 29.1% | 4,795 |
| 3 | Tyres | 21.5% | 3,550 |
| 4 | Emissions & environmental | 13.4% | 2,201 |
| 5 | Lighting & signalling | 11.9% | 1,959 |
| 6 | Other defects | 7.0% | 1,162 |
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 | 308 | 11.4% |
| 30-60k | 1,972 | 14.8% |
| 60-90k | 4,672 | 20.3% |
| 90-120k | 5,834 | 24.8% |
| 120-150k | 2,798 | 26.2% |
| 150k+ | 867 | 28.9% |
Failure rate by age
Trend over time
| Dataset year | Tests | Fail rate |
|---|---|---|
| 2021 | 3,709 | 24.0% |
| 2022 | 3,484 | 21.3% |
| 2023 | 3,380 | 23.9% |
| 2024 | 3,062 | 22.4% |
| 2025 | 2,853 | 20.8% |
What to check before buying a 2003 Z4
On a 2003 Z4, brakes is what the MOT record says goes wrong most — it appeared in 9.1% of tests. Check these areas before you commit.
- Brakes (9.1% 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.
- Suspension (9.0% 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 (8.5% 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 BMW Z4s pass their MOT?
77.5% of the 16,488 2003 BMW Z4 MOT tests in this dataset passed — a 22.6% fail rate.
What is the most common MOT failure on a 2003 BMW Z4?
Brakes, recorded in 9.1% of tests, followed by suspension (9.0%).
Does the 2003 Z4 get worse with mileage?
Its MOT fail rate rises from 11.4% in the 0-30k band to 28.9% in the 150k+ band.
Methodology & source. Based on 16,488 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.