2025 MOT results
BMW Z4 common problems
The most common reason a BMW Z4 fails its MOT is a tyre worn through to the cords, on 9.4% of its 7,834 failed tests in 2025. Against other cars of the same age, 4 faults stand out, the widest gaps being: the airbag light on at 6.5% of failures against 2.2% expected; a tyre worn through to the cords at 9.4% of failures against 4.4% expected; corroded brake pipes at 5.2% of failures against 2.9% expected.
- Tests in 2025 35,131 Cars aged three and over
- Failed first time 22.3% 7,834 tests
- Found a dangerous defect 7.0% Unsafe to drive away
- Ended with an advisory 45.6% A problem to watch, not a failure
What fails a BMW Z4 MOT
Each bar is the share of failed BMW Z4 tests with that defect. Where we can compare it with cars of the same registration years, the marker shows what an average car of those ages records (11 of the 12 items below).
Most common reasons for failure
A test can fail for more than one defect, so shares add up to more than 100%.
| Defect | Share of failed tests |
|---|---|
| Tyres: ply or cords exposed Tyres | 9.4% |
| Malfunction indicator lamp: inoperative or indicates a malfunction Noise, emissions and leaks | 8.5% |
| Coil spring: fractured or broken Suspension | 7.6% |
| Wipers: does not clear the windscreen effectively Visibility | 7.4% |
| SRS malfunction indicator lamp: warning lamp indicates a fault Seat belts and supplementary restraint systems | 6.5% |
| Tyres: tread depth below requirements of 1.6mm Tyres | 6.5% |
| Tyres: cut in excess of the requirements deep enough to reach the ply or cords Tyres | 6.3% |
| Washers: provides insufficient washer liquid Visibility | 5.2% |
| Rigid brake pipes: excessively corroded Brakes | 5.2% |
| Road wheels: fractured Road wheels | 5.0% |
| Suspension arms: ball joint excessively worn Suspension | 4.7% |
| Shock absorbers: serious fluid leak Suspension | 4.6% |
Source:DVSA,UK Motoring analysis 2025 Updated
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Tyre worn through to the cords
9.4% of failures 4.4% expected 2.1 times as often
The tyre is worn or damaged far enough to expose the cords underneath, which is a dangerous defect.
Run a hand round the inner and outer walls of each tyre, which is where kerbing shows.
-
Engine management light on
8.5% of failures 6.2% expected somewhat more often
The engine management light is on, or has been disconnected. Either fails the test.
A cheap code reader on the diagnostic socket will say what the car has stored before you pay for a test.
-
Broken coil spring
7.6% of failures 8.3% expected about as expected
A broken suspension spring, which usually snaps in the bottom coil and often fails on both sides within a year.
Look at each corner for a sagging ride height, and listen for a knock over speed bumps.
-
Wiper blades that do not clear the screen
7.4% of failures 6.5% expected about as expected
Wiper blades that leave the windscreen smeared or streaked across the area the driver looks through.
Look for split or hardened rubber, and lift each blade to see whether it still sits flat.
-
Airbag light on
6.5% of failures 2.2% expected 3 times as often
The airbag warning light shows a fault in the restraint system.
Common causes are a seat belt buckle sensor, or a wiring loom under a front seat.
-
Tyre worn below the legal limit
6.5% of failures 7.1% expected about as expected
A tyre worn past the 1.6mm legal minimum across the middle three quarters of the tread.
A 20p coin in the main grooves: if the outer band of the coin is visible, the tyre is close to the limit.
Which parts of the car fail
Suspension is the area that most often fails a BMW Z4, on 27.4% of failed tests. The widest gap against cars of the same registration years is tyres, on 26.3% against 19.3% expected.
Failure categories
DVSA's own sections of the test. The marker is what cars of the same registration years record.
| Defect category | Share of failed tests |
|---|---|
| Suspension | 27.4% |
| Lamps, reflectors and electrical equipment | 26.8% |
| Tyres | 26.3% |
| Brakes | 22.1% |
| Visibility | 16.0% |
| Noise, emissions and leaks | 13.4% |
| Seat belts and supplementary restraint systems | 7.0% |
| Road wheels | 6.6% |
Source:DVSA,UK Motoring analysis 2025 Updated
What testers warn about
45.6% of BMW Z4 tests ended with at least one advisory: a fault the tester found that did not fail the test. On BMW Z4s, these are the items to ask about on a car you are viewing, because they are what the last tester expected to go next.
Most common advisories
Share of all tests, passes included.
| Advisory | Share of tests |
|---|---|
| Tread depth: worn close to legal limit or worn on edge Tyres | 14.4% |
| Brake discs: worn, pitted or scored, but not seriously weakened Brakes | 8.2% |
| Rigid brake pipes: corroded, covered in grease or other material Brakes | 7.9% |
| Engine oil leak, but not excessive Noise, emissions and leaks | 7.6% |
| Tyres: slightly damaged or cracking or perishing Tyres | 6.8% |
| Brake pads: wearing thin Brakes | 4.4% |
| Suspension arms: pin or bush worn but not resulting in excessive movement Suspension | 3.4% |
| Shock absorbers: light misting of oil Suspension | 3.1% |
| Sub-frame: corroded but not seriously weakened Suspension | 2.9% |
| Coil spring: corroded Suspension | 2.8% |
| Suspension arms: ball joint has slight play Suspension | 2.3% |
| Flexible brake hoses: slightly deteriorated Brakes | 2.0% |
Source:DVSA,UK Motoring analysis 2025 Updated
What changes as a BMW Z4 gets older
A 2019 BMW Z4 failed 11.2% of its MOT tests in 2025; a 2003 one failed 31.0%. What fails changes as much as how often, and these are the two years themselves rather than an average across them.
2019 BMW Z4 11.2% failed, from 2,014 tests
- Tyre worn through to the cords 41.8%
- Cut tyre 19.6%
- Tyre worn below the legal limit 9.3%
- Headlamp aim set too high 5.3%
2003 BMW Z4 31.0% failed, from 2,362 tests
- Airbag light on 18.6%
- Corroded brake pipes 9.2%
- Wiper blades that do not clear the screen 9.0%
- Tyre worn below the legal limit 8.9%
- Worn steering or suspension joint 6.7%
- Engine management light on 6.1%
Shares are of each year's failed tests. Every MOT a particular car has had, with the defects and advisories written at each test, is on GOV.UK's MOT history service from the registration, free.
BMW Z4 problems: common questions
What is the most common problem with a BMW Z4?
Of the faults that fail an MOT, “Tyres: ply or cords exposed” is the most common: it appears on 9.4% of failed BMW Z4 tests. Across categories, suspension is the area that most often fails one, on 27.4% of failed tests.
How often does a BMW Z4 fail its MOT?
22.3% of BMW Z4 tests in 2025 were not passed first time, from 35,131 tests of cars aged three and over. Allowing for the age and mileage of the cars tested, that gives it a UK Motoring Reliability Score of 61 out of 100, where 50 is as expected.
Does anything fail more often on a BMW Z4 than on other cars?
Yes. “SRS malfunction indicator lamp: warning lamp indicates a fault” appears on 6.5% of its failures against 2.2% for cars of the same age, and “Tyres: ply or cords exposed” appears on 9.4% of its failures against 4.4% for cars of the same age. Where an item is missing from the national figures for a year, we use the smallest share those figures show, so the comparison never overstates the difference.
Are these the same as breakdowns or known faults?
No. These are the items a tester recorded at the MOT, which covers condition and safety: lamps, brakes, tyres, suspension, corrosion and emissions. A gearbox that is unpleasant, an infotainment screen that has died, or a car that will not start on a cold morning are not part of the test, so they are not in these figures.
Where do the figures come from?
Every normal MOT test of a BMW Z4 aged three and over in Great Britain in 2025, from DVSA's anonymised MOT results. Retests are excluded, and the same fault on more than one wheel counts once.
Data stories to read next
Data sources and methodology
| Figures | Source | Period | Records | Updated |
|---|---|---|---|---|
| MOT defects and advisories | Anonymised MOT tests and results Driver and Vehicle Standards Agency Derived statistics UK Motoring | 2025 | 35,131 MOT tests | 19 September 2026 |
- Shares for defects are of failed tests; shares for advisories are of all tests. A test can carry several defects, so shares add to more than 100%.
- The expected share is what an average car of the same registration years records, weighted by where this model’s failures fall. Where an item is outside the national figures for a year, the smallest share those figures show is used in its place, which is an upper bound, so the comparison never overstates a model’s problems. No expectation is published where less than 80% of the model’s failures can be compared.
- Great Britain only: DVSA does not run MOT testing in Northern Ireland. Cars under three years old are not tested.
- The descriptions of what each part does are general and the same on every model. Every figure comes from the MOT data.
Contains public sector information licensed under the Open Government Licence v3.0.