1998 Audi A8 — MOT failures & pass rate
Across 327 MOT tests, the 1998 Audi A8 recorded a 76.1% pass rate. Against executive cars of a similar age (22.8% fail rate), the 1998 A8 comes out 1.0pp worse. Failures cluster in lighting & signalling, suspension and brakes.
What the MOT record shows
No single area dominates — lighting & signalling (9.5%) and suspension (8.6%) are close, so failures are spread across several systems rather than one weak point.
At component level the recurring items are catalyst emissions, rbt (sp) and wipers — catalyst emissions alone was recorded 27 times.
Mileage matters less than usual here: the 1998 A8 fails 21.3% of the time in the 60-90k band and 22.6% at 150k+, a spread of only 1.4 points.
Advisories point at the next bill rather than this one: suspension was flagged on 36.7% of tests without failing them.
The trend is improving — the fail rate fell from 27.3% in 2021 to 25.0% in 2025, as the worst-kept examples leave the fleet.
How it compares
Top failure categories
| # | Category | % of tests affected | Tests |
|---|---|---|---|
| 1 | Lighting & signalling | 9.5% | 31 |
| 2 | Suspension | 8.6% | 28 |
| 3 | Brakes | 8.6% | 28 |
| 4 | Visibility | 6.4% | 21 |
| 5 | Body, structure & corrosion | 5.5% | 18 |
| 6 | Seat belts & restraints | 4.3% | 14 |
Most common specific failures
The exact components most often recorded as failures — more specific than the categories above.
| # | Failure item | Times recorded |
|---|---|---|
| 1 | Catalyst emissions | 27 |
| 2 | Rbt (sp) | 16 |
| 3 | Wipers | 15 |
| 4 | Joints | 14 |
| 5 | SRS malfunction indicator lamp | 12 |
| 6 | Ball joint | 12 |
Top advisory categories
Advisories aren't failures, but they flag work likely needed soon — useful when budgeting.
| # | Category | % of tests with advisory | Tests |
|---|---|---|---|
| 1 | Suspension | 36.7% | 120 |
| 2 | Brakes | 36.1% | 118 |
| 3 | Emissions & environmental | 23.8% | 78 |
| 4 | Tyres | 19.9% | 65 |
| 5 | Steering | 13.8% | 45 |
| 6 | Body, structure & corrosion | 12.5% | 41 |
Failure rate by mileage
Higher-mileage cars tend to fail more — often the most useful guide to real condition.
| Mileage band | Tests | Fail rate |
|---|---|---|
| 60-90k | 47 | 21.3% |
| 90-120k | 59 | 27.1% |
| 120-150k | 77 | 26.0% |
| 150k+ | 137 | 22.6% |
Failure rate by age
Trend over time
| Dataset year | Tests | Fail rate |
|---|---|---|
| 2021 | 99 | 27.3% |
| 2022 | 67 | 19.4% |
| 2023 | 69 | 26.1% |
| 2024 | 52 | 19.2% |
| 2025 | 40 | 25.0% |
What to check before buying a 1998 A8
On a 1998 A8, lighting & signalling is what the MOT record says goes wrong most — it appeared in 9.5% of tests. Check these areas before you commit.
- Lighting & signalling (9.5% of tests): Often a cheap bulb, but persistent issues can mean wiring or corrosion in the units. Typical repair: £10–£150.
- Suspension (8.6% of tests): Worn drop links, bushes, springs or shocks — listen for knocks over bumps and check for uneven tyre wear. Typical repair: £150–£450 per corner.
- Brakes (8.6% 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.
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 1998 Audi A8s pass their MOT?
76.1% of the 327 1998 Audi A8 MOT tests in this dataset passed — a 23.8% fail rate.
What is the most common MOT failure on a 1998 Audi A8?
Lighting & signalling, recorded in 9.5% of tests, followed by suspension (8.6%).
Does the 1998 A8 get worse with mileage?
Its MOT fail rate rises from 21.3% in the 60-90k band to 22.6% in the 150k+ band.
Methodology & source. Based on 327 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.