2003 Audi A6 diesel: common problems and MOT failures

What goes wrong more than usual on a 2003 Audi A6 diesel?

Parts flagged at MOT more often on the 2003 Audi A6 diesel than on all cars registered in 2003.

• Suspension arm bushes and joints3× usual
  Audi A6

  25.7% All 2003 cars

  8.6%

  Failed outright at MOT: 6.9%, against 1.9% of all 2003 cars. The rest were advisories or minor defects.

  Rough price £120–£180 (one arm) ClickMechanic

  At the viewing: Listen for clunks over bumps and feel for the steering wandering. Worn arm bushes show as cracked rubber near the wheels.

• Drive shaft (CV) joints3× usual
  Audi A6

  19.8% All 2003 cars

  6.6%

  Failed outright at MOT: 9%, against 2.9% of all 2003 cars. The rest were advisories or minor defects.

  Rough price £60–£350 our estimate

  At the viewing: Drive slowly on full steering lock in both directions and listen for clicking. Look for split rubber boots behind the front wheels.

• Brake discs1.7× usual
  Audi A6

  22.2% All 2003 cars

  12.8%

  Failed outright at MOT: 2%, against 0.9% of all 2003 cars. The rest were advisories or minor defects.

  Rough price £150–£350 our estimate

  At the viewing: Look through the wheel at the brake disc: a deep lip at the edge or heavy scoring means they're worn. Feel for judder when braking.

• Ball joint1.9× usual
  Audi A6

  12.3% All 2003 cars

  6.4%

  Failed outright at MOT: 5.8%, against 3% of all 2003 cars. The rest were advisories or minor defects.

  Rough price £60–£150 (one joint) ClickMechanic

  At the viewing: Listen for knocking over bumps and check the rubber boots behind the wheels aren't split.

• Track rod ends1.8× usual
  Audi A6

  11.6% All 2003 cars

  6.3%

  Failed outright at MOT: 3.8%, against 2.8% of all 2003 cars. The rest were advisories or minor defects.

  Rough price £50–£150 (one end, plus about £30–£50 if it needs a wheel alignment) ClickMechanic

  At the viewing: On a straight road the steering wheel should sit straight. Listen for knocks when turning, and check the steering feels even.

Common 2003 Audi A6 diesel MOT failures and advisories

The share of 2003 Audi A6 diesel MOT tests where testers flagged each area, as a fail or an advisory. Rough prices are typical independent-garage costs.

• Suspension
  55% 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
  47% 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
  41% of testsRough price £10–£80

  At the viewing: Ask a friend to check every light, including brake lights and indicators, while you operate them.

• Tyres
  34% 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.

• Oil and fluid leaks
  24% of testsRough price £80–£600

  At the viewing: Look under the engine and on the ground where the car is usually parked for fresh oil or fluid.

• Driveshafts and joints
  20% of testsRough price £60–£350

  At the viewing: On full steering lock, drive slowly and listen for clicking from the front wheels.

Questions to ask the seller before buying a 2003 Audi A6 diesel

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

1. Any recent work on the suspension arm bushes and joints? (Flagged at MOT 3× as often on the 2003 Audi A6 diesel as on other cars the same age.)
2. Any recent work on the drive shaft (cv) joints? (Flagged at MOT 3× as often on the 2003 Audi A6 diesel as on other cars the same age.)
3. Any recent work on the brake discs? (Flagged at MOT 1.7× as often on the 2003 Audi A6 diesel as on other cars the same age.)
4. Can I see the service history and receipts for any big jobs?