BMW 340i — MOT pass rate & failures
The BMW 340i passed 92.6% of its 4,864 MOT tests, covering model years 2015–2022. That is 10.0 percentage points better than the 17.4% fail rate across all BMW 3 Series versions, so the 340i is a stronger pick within the range. Failures concentrate in tyres, lighting & signalling and visibility.
What the MOT record shows
At component level the recurring items are tread depth, headlamp aim and catalyst emissions — tread depth alone was recorded 76 times.
Mileage is the strongest signal on the record: 4.7% of 0-30k cars fail, rising to 16.2% once past 120-150k — 3.5× the risk.
Advisories point at the next bill rather than this one: tyres was flagged on 15.4% of tests without failing them.
How it compares
By model year
| Year | Tests | Pass rate | Fail rate |
|---|---|---|---|
| 2016 | 703 | 93.0% | 7.0% |
| 2017 | 2,646 | 92.2% | 7.8% |
| 2018 | 1,108 | 93.5% | 6.5% |
| 2019 | 376 | 93.1% | 6.9% |
Top failure categories
| # | Category | % of tests affected | Tests |
|---|---|---|---|
| 1 | Tyres | 5.3% | 256 |
| 2 | Lighting & signalling | 1.4% | 69 |
| 3 | Visibility | 0.7% | 34 |
| 4 | Brakes | 0.5% | 24 |
| 5 | Suspension | 0.5% | 24 |
| 6 | Road wheels | 0.4% | 19 |
| 7 | Emissions & environmental | 0.4% | 18 |
| 8 | Other defects | 0.3% | 13 |
Most common specific failures
The exact components most often recorded as failures — more specific than the categories above.
| # | Failure item | Times recorded |
|---|---|---|
| 1 | Tread depth | 76 |
| 2 | Headlamp aim | 57 |
| 3 | Catalyst emissions | 28 |
| 4 | Registration plates | 21 |
| 5 | Washers | 19 |
| 6 | Shock absorbers | 18 |
Top advisory categories
Advisories aren't failures, but they flag work likely needed soon — useful when budgeting.
| # | Category | % of tests with advisory | Tests |
|---|---|---|---|
| 1 | Tyres | 15.4% | 751 |
| 2 | Brakes | 6.5% | 315 |
| 3 | Other defects | 5.5% | 270 |
| 4 | Visibility | 2.6% | 128 |
| 5 | Suspension | 2.3% | 112 |
| 6 | Steering | 1.1% | 55 |
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 | 1,544 | 4.7% |
| 30-60k | 2,360 | 8.3% |
| 60-90k | 777 | 8.5% |
| 90-120k | 140 | 12.1% |
| 120-150k | 37 | 16.2% |
Failure rate by age
Trend over time
| Dataset year | Tests | Fail rate |
|---|---|---|
| 2021 | 914 | 6.9% |
| 2022 | 991 | 7.3% |
| 2023 | 986 | 6.5% |
| 2024 | 970 | 8.6% |
| 2025 | 1,003 | 7.7% |
What to check before buying a BMW 340i
Focus on the areas it most often fails on — and remember MOT data covers testable defects only, not engine or gearbox health.
- Tyres (5.3% of tests): Usually a quick, known-cost fix, but check tread, age and uneven wear (which can hint at alignment or suspension issues). Typical repair: £50–£120 per tyre.
- Lighting & signalling (1.4% of tests): Often a cheap bulb, but persistent issues can mean wiring or corrosion in the units. Typical repair: £10–£150.
- Visibility (0.7% of tests): Wipers, washers, mirrors and screen damage — usually inexpensive, but check for chips in the driver's line of sight. Typical repair: £15–£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 reliable is the BMW 340i at MOT time?
92.6% of the 4,864 BMW 340i MOT tests in this dataset passed — a 7.4% fail rate, better than the 17.4% average across all 3 Series versions.
What is the most common MOT failure on a BMW 340i?
Tyres, recorded in 5.3% of tests, followed by lighting & signalling (1.4%).
Does the 340i get worse with mileage?
Its MOT fail rate rises from 4.7% in the 0-30k band to 16.2% in the 120-150k band.
Methodology & source. Based on 4,864 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.