2018 SEAT Leon diesel: common problems and MOT failures

What goes wrong more than usual on a 2018 SEAT Leon diesel?

Parts flagged at MOT more often on the 2018 SEAT Leon diesel than on all cars registered in 2018.

• Shock absorbers9.1× usual
  SEAT Leon

  20.9% All 2018 cars

  2.3%

  Failed outright at MOT: 2.4%, against 0.4% of all 2018 cars. The rest were advisories or minor defects.

  Rough price £200–£300 (pair, average rear to front) ClickMechanic

  At the viewing: Push down hard on each corner. It should bounce once and settle. Look for oil on the shock absorber body.

• Coil springs2.9× usual
  SEAT Leon

  3.2% All 2018 cars

  1.1%

  Failed outright at MOT: 2.7%, against 0.9% of all 2018 cars. The rest were advisories or minor defects.

  Rough price £175–£400 (pair, one axle) ClickMechanic

  At 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 SEAT Leon diesel MOT failures and advisories

The share of 2018 SEAT Leon diesel MOT tests where testers flagged each area, as a fail or an advisory. Rough prices are typical independent-garage costs.

• Tyres
  30% 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.

• Suspension
  24% 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.

• Brakes
  22% 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.

• Lights and electrics
  7% 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 mirrors
  6% of testsRough price £15–£250

  At the viewing: Check for chips in the driver's view, and test the wipers and washers.

• Seats and seatbelts
  3% of testsRough price £80–£250

  At the viewing: Pull each seatbelt sharply. It should lock, and retract cleanly.

Known faults on the 2018 SEAT Leon 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.

• DSG automatic needs regular oil changes

  DSG automatic

  The DSG automatic needs its oil and filter changing about every 40,000 miles. Cars serviced away from dealers or specialists sometimes miss it, which can lead to expensive gearbox faults.

  At the viewing: Look in the service history for a DSG oil change. Pull away gently several times and check for judder.

  If it needs doing: Gearbox sensor or solenoid, about £200–£500. ClickMechanic

  Source: Parkers: used SEAT Leon review

• Notchy manual gearbox

  Manual gearbox

  Some owners report stiff or notchy changes in certain gears. A healthy Leon gearbox should slot into every gear with very little effort.

  At the viewing: On the test drive, go up and down through every gear, including reverse. Stiffness or crunching isn't normal.

  If it needs doing: Gearbox sensor or solenoid, about £200–£500. ClickMechanic

  Source: Parkers: used SEAT Leon review

• Leaky rear light seals

  All engines

  The seals on the rear light units can let water in. Condensation inside the lens is the first sign, and enough water can make the lights fail, which is an MOT fail.

  At the viewing: Look inside both rear lights for misting or water droplets, and check every bulb works.

  Source: Parkers: used SEAT Leon review

Questions to ask the seller before buying a 2018 SEAT Leon diesel

Ask before you travel to see it. A seller who knows the car will have answers, and receipts.

1. When was the DSG gearbox oil last changed?
2. Has the gearbox or clutch had any work?
3. Have the rear lights ever been replaced or resealed?
4. Any recent work on the shock absorbers? (Flagged at MOT 9.1× as often on the 2018 SEAT Leon diesel as on other cars the same age.)
5. Any recent work on the coil springs? (Flagged at MOT 2.9× as often on the 2018 SEAT Leon diesel as on other cars the same age.)
6. Can I see the service history and receipts for any big jobs?