2018 Audi A1 diesel: common problems and MOT failures
What MOT testers find on the diesel Audi A1 first registered in 2018 (diesel cars only): we looked at the 3,115 MOTs these cars had during 2023–2025. Plus known faults and what to look at before you buy one.
What goes wrong more than usual on a 2018 Audi A1 diesel?
Parts flagged at MOT more often on the 2018 Audi A1 diesel than on all cars registered in 2018.
- Suspension arm bushes and joints5.1× usualAudi A111.7% All 2018 cars2.3%
Failed outright at MOT: 4.5%, against 0.4% of all 2018 cars. The rest were advisories or minor defects.
Rough price £120–£180 (one arm) ClickMechanicAt the viewing: Listen for clunks over bumps and feel for the steering wandering. Worn arm bushes show as cracked rubber near the wheels.
- Coil springs1.9× usualAudi A12.1% All 2018 cars1.1%
Failed outright at MOT: 1.7%, against 0.8% of all 2018 cars. The rest were advisories or minor defects.
Rough price £175–£400 (pair, one axle) ClickMechanicAt the viewing: Look behind each wheel for a snapped spring coil, and listen for a clunk or twang when turning the wheel lock to lock with the car stopped.
Common 2018 Audi A1 diesel MOT failures and advisories
The share of 2018 Audi A1 diesel MOT tests where testers flagged each area, as a fail or an advisory. Rough prices are typical independent-garage costs.
- Tyres33% of testsRough price £70–£150
At the viewing: Check the tread on all four tyres, including the inside edges, and look for cracks or bulges.
- Brakes20% of testsRough price £150–£350
At the viewing: Look for a lip on the disc edges and feel for judder or pulling when braking firmly from about 40mph.
- Suspension16% of testsRough price £120–£400
At the viewing: Listen for knocks over speed bumps, and look behind each front wheel for a snapped coil spring.
- Lights and electrics6% of testsRough price £10–£80
At the viewing: Ask a friend to check every light, including brake lights and indicators, while you operate them.
- Wipers, windscreen and mirrors4% of testsRough price £15–£250
At the viewing: Check for chips in the driver's view, and test the wipers and washers.
- Seats and seatbelts2% of testsRough price £80–£250
At the viewing: Pull each seatbelt sharply. It should lock, and retract cleanly.
Known faults on the 2018 Audi A1 diesel
Reported by owners, mechanics and buying guides for this model and age. Check which engine the car has, as some apply to one engine only.
- 1.6 TDI diesel
Blocked DPF and rising oil (1.6 TDI)
The 1.6 diesel's particulate filter needs high-speed runs to clean itself. Interrupted cleaning can also put fuel into the oil, so the oil level rises.
At the viewing: Ask how the car is used, and check the dipstick: oil above the top mark or smelling of diesel is a bad sign.
If it needs doing: DPF clean or regeneration, about £160–£500. ClickMechanic
- All engines
Bluetooth and small electrical faults
Phone pairing can drop out and there are some niggly electrical faults.
At the viewing: Pair your own phone on the test drive.
- All engines
Kerbed alloys
A1s spend a lot of time in towns, so kerbed or cracked wheels are common.
At the viewing: Check each wheel rim for scuffs and cracks.
Questions to ask the seller before buying a 2018 Audi A1 diesel
Ask before you travel to see it. A seller who knows the car will have answers, and receipts.
- Has it done regular motorway runs, and has the DPF been cleaned?
- Have there been any electrical faults?
- Have the wheels been refurbished?
- Any recent work on the suspension arm bushes and joints? (Flagged at MOT 5.1× as often on the 2018 Audi A1 diesel as on other cars the same age.)
- Any recent work on the coil springs? (Flagged at MOT 1.9× as often on the 2018 Audi A1 diesel as on other cars the same age.)
- Can I see the service history and receipts for any big jobs?
Looking at an Audi A1?
Check the actual car: its own MOT history, mileage and what to ask the seller. Free, no sign-up.
Other years
Every year of the Audi A1 compared
| Year | MOT tests | Most flagged |
|---|---|---|
| 2026 | – | Too new for MOT data |
| 2025 | – | Too new for MOT data |
| 2024 | – | Too new for MOT data |
| 2023 | 984 | Tyres 16% |
| 2022 | 15,755 | Tyres 26% |
| 2021 | 28,674 | Tyres 29% |
| 2020 | 39,764 | Tyres 27% |
| 2019 | 60,535 | Tyres 29% |
| 2017 | 68,163 | Tyres 33% |
| 2016 | 75,827 | Tyres 33% |
| 2015 | 70,503 | Tyres 33% |
| 2014 | 68,304 | Tyres 34% |
| 2013 | 66,272 | Tyres 35% |
| 2012 | 54,835 | Tyres 35% |
| 2011 | 48,250 | Suspension 39% |
| 2010 | 4,170 | Suspension 43% |
Where this comes from: the DVSA's anonymised results for every MOT test done in Great Britain during 2023–2025, counting the MOTs of Audi A1 cars first registered in 2018. "Flagged" includes advisories, so it isn't the same as a fail rate. How we score