2004 · 20 years old at test · Petrol mostly

2004 Porsche 911 MOT pass rate and common faults

2,338 MOT tests in 2024. 83.1% passed first time, compared with 56.4% for all cars the same age.

147Well above average
Passed first time83.1%
Failed or needed repairs16.9%
Typical mileage at test72,000

Most common reasons for failing

Share of all 2,338 tests where this item caused a failure.

  1. Catalyst emissions: Lambda reading after 2nd fast idle outside specified limits2.6%
  2. Rigid brake pipes: excessively corroded1.8%
  3. Joints: constant velocity boot split or insecure, no longer prevents the ingress of dirt1.4%
  4. Position lamp: not working1.3%
  5. Tyres - condition: has ply or cords exposed1.2%
    47 marked dangerous
  6. Wipers: does not clear the windscreen effectively0.9%
  7. Tread depth below requirements of 1.6mm0.9%
    31 marked dangerous
  8. Exhaust system: has a major leak of exhaust gases0.9%
  9. Headlamp aim: too high0.9%
  10. Brake performance not tested: unable to be tested0.6%

Problem areas

Failure items found per 100 tests, by part of the car.

  1. Lights & electrics8.2%
  2. Brakes5.4%
  3. Emissions & leaks5.0%
  4. Tyres3.5%
  5. Body & chassis2.7%
  6. Suspension2.4%
  7. Visibility (wipers, screen, mirrors)2.0%
  8. Number plates & VIN0.6%

Most common advisories

Not failures yet, but things the tester warned about.

  1. Rigid brake pipes: excessively corroded12.0%
  2. Tread depth below requirements of 1.6mm8.2%
  3. Brake discs: in such a condition that it is seriously weakened8.1%
  4. Tyres - condition: has a tear, caused by separation or partial failure of its structure4.1%
  5. Engine oil leaks: leaking excessively from engine3.9%

What this means if you are buying one

This model year does better than most cars its age, so it is a reasonable used buy on MOT record alone. Before buying, check the area that fails most: catalyst emissions: lambda reading after 2nd fast idle outside specified limits. Then look up the car's own MOT history on GOV.UK with its number plate, and look for repeat advisories.

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Questions

What is the MOT pass rate for a 2004 Porsche 911?

In 2024, 83.1% of 2004 Porsche 911 cars passed their MOT first time, across 2,338 tests. The average for all 20-year-old cars was 56.4%.

What are the most common MOT failures on a 2004 Porsche 911?

The most common failure reasons were catalyst emissions: lambda reading after 2nd fast idle outside specified limits; rigid brake pipes: excessively corroded; joints: constant velocity boot split or insecure, no longer prevents the ingress of dirt. The biggest problem area was lights & electrics.

Is the 2004 Porsche 911 reliable at MOT time?

Its MOT Rank score is 147, which is well above average for a car of its age (100 means exactly average).