MG B MOT failures and reliability
In 2023 the MG B took 4,590 MOT tests in Britain and passed 79% of them first time, above the national average of 71% for all cars. The figures below come from the DVSA's record of every test, so they show what testers actually found on these cars rather than what owners report.
- MOT tests in 2023
- 4,590
- First-time pass rate
- 79%
- All cars
- 71%
What the B fails on
Share of tests with at least one failure in each area, against the figure for all cars.
- Lights and electrics10.2% (all cars 11.3%)
- Brakes7.1% (all cars 6.8%)
- Visibility5.1% (all cars 4.8%)
- Exhaust and emissions3.6% (all cars 3.1%)
- Suspension3.5% (all cars 9.0%)
- Body and structure3.1% (all cars 3.5%)
- Steering3.1% (all cars 1.8%)
- Tyres0.8% (all cars 6.4%)
Most common failure items
Share of tests on which each item was recorded.
- Service brake imbalance: across an axle 2.8%
- Non catalyst emissions: emissions carbon monoxide content excessive 2.7%
- Washers: not working 2.2%
- Position lamp: not working 2.1%
- Horn: not working 1.8%
- Steering rack: gaiter missing or no longer prevents the ingress of dirt 1.8%
- Service brake performance: excessively binding 1.7%
- Stop lamp: all not working 1.6%
Most common advisories
- Engine oil leaks: leak, but not excessive 10.7%
- Wheel bearings: has slight play 5.1%
- Transmission oil leaks: leak, but not excessive 3.0%
- Shock absorbers: has light misting of oil 2.8%
- Suspension arms, pins and bushes: pin or bush worn but not resulting in excessive movement 2.8%
- Tyres, condition: slightly damaged/cracking or perishing 2.6%
- Rigid brake pipes: corroded, covered in grease or other material 2.5%
- Service brake performance: binding but not excessively 2.3%
Pass rate by year of registration
Older cars fail more often whatever the model, so compare a car with others of the same age.
| First registered | Tests | Pass rate |
|---|---|---|
| 1970 | 301 | 84% |
| 1971 | 396 | 79% |
| 1972 | 530 | 80% |
| 1973 | 450 | 84% |
| 1974 | 363 | 78% |
| 1978 | 311 | 74% |
Check a particular B
Model figures tell you what to look out for. To see one car's own MOT history, mileage and tax, enter its registration.
Other MG models
Source: Department for Transport, Anonymised MOT tests and results, 2023, cars and light vans, normal tests only. Pass rates are first-time passes; a pass after repair at the test station counts as a fail. Contains public sector information licensed under the Open Government Licence v3.0.