2018 Kia Stonic — MOT failures & pass rate
37,168 MOT tests on the 2018 Kia Stonic are in this dataset, and 91.8% of them passed. Small SUVs of a similar age fail 9.9% of the time, so this is 1.6pp better than the group it competes with. Failures cluster in visibility, brakes and tyres.
What the MOT record shows
No single area dominates — visibility (3.8%) and brakes (3.0%) are close, so failures are spread across several systems rather than one weak point.
At component level the recurring items are wipers, brake pads and tread depth — wipers alone was recorded 1,298 times.
Mileage is the strongest signal on the record: 4.5% of 0-30k cars fail, rising to 22.4% once past 120-150k — 4.9× the risk.
The petrol cars hold up better: 7.8% fail against 9.7% for diesel, a 1.9-point gap across 37,168 tests.
Tyres is the most common advisory, noted on 19.3% of tests — work that passed today but is likely due soon.
The trend is worsening — 4.2% of tests failed in 2021 against 10.7% in 2025, the usual pattern as a fleet ages.
How it compares
Top failure categories
| # | Category | % of tests affected | Tests |
|---|---|---|---|
| 1 | Visibility | 3.8% | 1,406 |
| 2 | Brakes | 3.0% | 1,127 |
| 3 | Tyres | 2.6% | 970 |
| 4 | Lighting & signalling | 1.9% | 711 |
| 5 | Suspension | 0.6% | 223 |
| 6 | Emissions & environmental | 0.5% | 201 |
Most common specific failures
The exact components most often recorded as failures — more specific than the categories above.
| # | Failure item | Times recorded |
|---|---|---|
| 1 | Wipers | 1,298 |
| 2 | Brake pads | 974 |
| 3 | Tread depth | 716 |
| 4 | Washers | 379 |
| 5 | Headlamp aim | 361 |
| 6 | Headlamp | 340 |
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 | 19.3% | 7,175 |
| 2 | Brakes | 16.8% | 6,235 |
| 3 | Other defects | 7.7% | 2,855 |
| 4 | Visibility | 2.8% | 1,026 |
| 5 | Suspension | 1.2% | 443 |
| 6 | Emissions & environmental | 0.8% | 302 |
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 | 16,476 | 4.5% |
| 30-60k | 16,741 | 10.2% |
| 60-90k | 3,495 | 15.1% |
| 90-120k | 388 | 15.5% |
| 120-150k | 49 | 22.4% |
Failure rate by age
By fuel type
| Fuel | Tests | Fail rate |
|---|---|---|
| Petrol | 28,463 | 7.8% |
| Diesel | 8,705 | 9.7% |
Trend over time
| Dataset year | Tests | Fail rate |
|---|---|---|
| 2021 | 7,255 | 4.2% |
| 2022 | 7,366 | 6.8% |
| 2023 | 7,531 | 9.3% |
| 2024 | 7,479 | 10.2% |
| 2025 | 7,537 | 10.7% |
What to check before buying a 2018 Stonic
The failure pattern for this year is specific enough to inspect against: visibility accounted for 3.8% of tests. Start there.
- Visibility (3.8% 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.
- Brakes (3.0% 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.
- Tyres (2.6% 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.
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 2018 Kia Stonics pass their MOT?
91.8% of the 37,168 2018 Kia Stonic MOT tests in this dataset passed — a 8.3% fail rate.
What is the most common MOT failure on a 2018 Kia Stonic?
Visibility, recorded in 3.8% of tests, followed by brakes (3.0%).
Does the 2018 Stonic get worse with mileage?
Its MOT fail rate rises from 4.5% in the 0-30k band to 22.4% in the 120-150k band.
Methodology & source. Based on 37,168 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.