2018 Infiniti Q50 — MOT failures & pass rate
1,528 MOT tests on the 2018 Infiniti Q50 are in this dataset, and 86.3% of them passed. Executive cars of a similar age fail 10.8% of the time, so this is 2.9pp worse than the group it competes with. Failures cluster in brakes, tyres and visibility.
What the MOT record shows
No single area dominates — brakes (7.0%) and tyres (5.1%) are close, so failures are spread across several systems rather than one weak point.
At component level the recurring items are brake pads, tread depth and wipers — brake pads alone was recorded 118 times.
Condition tracks the odometer closely. Failures run at 12.9% in the 0-30k band and 18.6% in the 90-120k band, a 5.8-point spread.
Advisories point at the next bill rather than this one: brakes was flagged on 22.3% of tests without failing them.
The trend is worsening — 11.8% of tests failed in 2021 against 14.2% in 2025, the usual pattern as a fleet ages.
How it compares
Top failure categories
| # | Category | % of tests affected | Tests |
|---|---|---|---|
| 1 | Brakes | 7.0% | 107 |
| 2 | Tyres | 5.1% | 78 |
| 3 | Visibility | 2.3% | 35 |
| 4 | Suspension | 2.1% | 32 |
| 5 | Lighting & signalling | 1.8% | 27 |
| 6 | Emissions & environmental | 0.7% | 11 |
Most common specific failures
The exact components most often recorded as failures — more specific than the categories above.
| # | Failure item | Times recorded |
|---|---|---|
| 1 | Brake pads | 118 |
| 2 | Tread depth | 40 |
| 3 | Wipers | 34 |
| 4 | Brake discs | 22 |
| 5 | Ball joint | 19 |
| 6 | Wheel bearings | 13 |
Top advisory categories
Advisories aren't failures, but they flag work likely needed soon — useful when budgeting.
| # | Category | % of tests with advisory | Tests |
|---|---|---|---|
| 1 | Brakes | 22.3% | 341 |
| 2 | Tyres | 20.9% | 319 |
| 3 | Suspension | 12.2% | 186 |
| 4 | Other defects | 5.9% | 90 |
| 5 | Visibility | 2.9% | 45 |
| 6 | Emissions & environmental | 2.0% | 30 |
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 | 450 | 12.9% |
| 30-60k | 696 | 12.6% |
| 60-90k | 307 | 16.3% |
| 90-120k | 59 | 18.6% |
Failure rate by age
By fuel type
| Fuel | Tests | Fail rate |
|---|---|---|
| Diesel | 1,401 | 13.8% |
| Petrol | 98 | 14.3% |
Trend over time
| Dataset year | Tests | Fail rate |
|---|---|---|
| 2021 | 315 | 11.8% |
| 2022 | 300 | 11.3% |
| 2023 | 315 | 16.8% |
| 2024 | 310 | 14.2% |
| 2025 | 288 | 14.2% |
What to check before buying a 2018 Q50
On a 2018 Q50, brakes is what the MOT record says goes wrong most — it appeared in 7.0% of tests. Check these areas before you commit.
- Brakes (7.0% 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 (5.1% 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.
- Visibility (2.3% 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 many 2018 Infiniti Q50s pass their MOT?
86.3% of the 1,528 2018 Infiniti Q50 MOT tests in this dataset passed — a 13.7% fail rate.
What is the most common MOT failure on a 2018 Infiniti Q50?
Brakes, recorded in 7.0% of tests, followed by tyres (5.1%).
Does the 2018 Q50 get worse with mileage?
Its MOT fail rate rises from 12.9% in the 0-30k band to 18.6% in the 90-120k band.
Methodology & source. Based on 1,528 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.