2005 Mazda MX-5: common problems and MOT failures

What goes wrong more than usual on a 2005 Mazda MX-5?

Parts flagged at MOT more often on the 2005 Mazda MX-5 than on all cars registered in 2005.

• Rust around suspension or steering mountings1.8× usual
  Mazda MX-5

  10.1% All 2005 cars

  5.5%

  Failed outright at MOT: 5.6%, against 2.6% of all 2005 cars. The rest were advisories or minor defects.

  Rough price £100–£450 our estimate

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

• Suspension arm2.3× usual
  Mazda MX-5

  8.1% All 2005 cars

  3.5%

  Failed outright at MOT: 0.2%, against 0.4% of all 2005 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.

• Rust in key structural areas4.4× usual
  Mazda MX-5

  5.7% All 2005 cars

  1.3%

  Failed outright at MOT: 3.7%, against 0.9% of all 2005 cars. The rest were advisories or minor defects.

  Rough price £80–£250 our estimate

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

• Chassis rust or damage2.3× usual
  Mazda MX-5

  7.5% All 2005 cars

  3.2%

  Failed outright at MOT: 2.8%, against 0.9% of all 2005 cars. The rest were advisories or minor defects.

  Rough price £150–£1,000 our estimate

  At the viewing: Check the sills, wheel arches and underneath for rust, and look along the panels for uneven gaps or paint.

• Body structure rust or damage2.5× usual
  Mazda MX-5

  6.9% All 2005 cars

  2.8%

  Failed outright at MOT: 2.2%, against 0.8% of all 2005 cars. The rest were advisories or minor defects.

  Rough price £150–£1,000 our estimate

  At the viewing: Look underneath and along the sills for flaky rust or fresh underseal hiding it.

Common 2005 Mazda MX-5 MOT failures and advisories

The share of 2005 Mazda MX-5 MOT tests where testers flagged each area, as a fail or an advisory. Rough prices are typical independent-garage costs.

• Suspension
  36% 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
  34% 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
  20% 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
  18% 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.

• Rust and bodywork
  18% of testsRough price £150–£1,000

  At the viewing: Check the sills, wheel arches and underneath for rust, and look along the panels for uneven gaps or paint.

• Oil and fluid leaks
  10% 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.

Known faults on the 2005 Mazda MX-5

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.

• Rear differential whine

  All engines

  Wear inside the rear differential makes it whine. The fix is a replacement differential.

  At the viewing: Listen for whining from the back at a steady speed and when lifting off.

  Source: Haynes: Mazda MX-5 NC common problems (2005-2015)

• Sticking brake calipers

  All engines

  On cars that aren’t used much, brake calipers stick, so the car pulls when braking and one wheel runs hot.

  At the viewing: Brake firmly and feel for pulling.

  Source: Haynes: Mazda MX-5 NC common problems (2005-2015)

• Misfire with engine light

  All engines

  A misfire under acceleration with the engine light on can be a faulty crankcase ventilation hose.

  At the viewing: Accelerate hard and watch for warning lights.

  Source: Haynes: Mazda MX-5 NC common problems (2005-2015)

• Surging at idle

  All engines

  A dirty throttle body makes it stutter or surge when slowing and at idle.

  At the viewing: Let it idle and listen for hunting revs.

  Source: Haynes: Mazda MX-5 NC common problems (2005-2015)

Questions to ask the seller before buying a 2005 Mazda MX-5

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

1. Any recent work on the rust around suspension or steering mountings? (Flagged at MOT 1.8× as often on the 2005 Mazda MX-5 as on other cars the same age.)
2. Any recent work on the suspension arm? (Flagged at MOT 2.3× as often on the 2005 Mazda MX-5 as on other cars the same age.)
3. Any recent work on the rust in key structural areas? (Flagged at MOT 4.4× as often on the 2005 Mazda MX-5 as on other cars the same age.)
4. Can I see the service history and receipts for any big jobs?