2021 Kia Stonic Gt-Line S Isg Mhev — MOT failures & pass rate
Across 1,899 MOT tests analysed for the 2021 Kia Stonic Gt-Line S Isg Mhev, the most common recorded failure areas were visibility, tyres and lighting & signalling. Its pass rate of 95.4% was above the average for cars of a similar age (91.2%).
How it compares
Top failure categories
| # | Category | % of tests affected | Tests |
|---|---|---|---|
| 1 | Visibility | 2.5% | 47 |
| 2 | Tyres | 1.7% | 32 |
| 3 | Lighting & signalling | 1.4% | 26 |
| 4 | Brakes | 1.3% | 25 |
| 5 | Steering | 0.3% | 5 |
| 6 | Emissions & environmental | 0.2% | 4 |
Most common specific failures
The exact components most often recorded as failures — more specific than the categories above.
| # | Failure item | Times recorded |
|---|---|---|
| 1 | Wipers | 45 |
| 2 | Headlamp aim | 30 |
| 3 | Brake pads | 21 |
| 4 | Tread depth | 18 |
| 5 | Washers | 9 |
| 6 | Track rod end | 5 |
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 | 12.3% | 234 |
| 2 | Brakes | 8.1% | 154 |
| 3 | Other defects | 5.1% | 97 |
| 4 | Visibility | 4.0% | 75 |
| 5 | Steering | 1.4% | 26 |
| 6 | Suspension | 0.3% | 6 |
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 | 1,431 | 3.4% |
| 30-60k | 448 | 8.7% |
Failure rate by age
Trend over time
| Dataset year | Tests | Fail rate |
|---|---|---|
| 2024 | 916 | 3.6% |
| 2025 | 962 | 5.6% |
What to check before buying a 2021 Stonic Gt-Line S Isg Mhev
Before buying a 2021 Kia Stonic Gt-Line S Isg Mhev, focus on the areas it most often fails on. Visibility accounted for 2.5% of tests for this year.
- Visibility (2.5% 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.
- Tyres (1.7% 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.
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 2021 Kia Stonic Gt-Line S Isg Mhevs pass their MOT?
95.4% of the 1,899 2021 Kia Stonic Gt-Line S Isg Mhev MOT tests in this dataset passed — a 4.6% fail rate.
What is the most common MOT failure on a 2021 Kia Stonic Gt-Line S Isg Mhev?
Visibility, recorded in 2.5% of tests, followed by tyres (1.7%).
Does the 2021 Stonic Gt-Line S Isg Mhev get worse with mileage?
Its MOT fail rate rises from 3.4% in the 0-30k band to 8.7% in the 30-60k band.
Methodology & source. Based on 1,899 MOT tests. Dataset: DVSA MOT testing data (2021,2022,2023,2024,2025). Data last updated 2026-07-01. Figures reflect MOT-testable defects only — read the methodology for how these are calculated and what they don't measure.