The picture
Boxster: above-average pass rates, with caveats
Across 37,183 MOT tests, the Boxster returns 83.4% first-time pass — above the UK fleet average. The single most-logged Major fail is a corroded brake pipe. Lambda coefficient outside the default limits and windscreen damage round out the top three. Average tested mileage sits at 65,678, which is the lens to read those failure rankings through. If you own one and the next test is close, the ranked list below is a sensible pre-test checklist.
Top ten reasons for rejection.
- 01
Brake pipe damaged or excessively corroded
1,072 occurrences · 2.9% of tests
- 02
Lambda coefficient outside the default limits or the range specified by the manufacturer
1,000 occurrences · 2.7% of tests
- 03
Windscreen or window damaged or seriously discoloured but not adversely affecting driver's view
791 occurrences · 2.1% of tests
- 04
A spring or spring component fractured or seriously weakened
738 occurrences · 2.0% of tests
- 05
A rear registration plate lamp or light source missing or inoperative in the case of multiple lamps or light sources
637 occurrences · 1.7% of tests
- 06
Headlamp reflector or lens slightly defective
616 occurrences · 1.7% of tests
- 07
Tyre tread depth not in accordance with the requirements
597 occurrences · 1.6% of tests
- 08
A transmission shaft constant velocity joint boot severely deteriorated
463 occurrences · 1.2% of tests
- 09
The aim of a headlamp is not within limits laid down in the requirements
446 occurrences · 1.2% of tests
- 10
A lamp missing, inoperative or in the case of a multiple light source more than 1/2 not functioning
375 occurrences · 1.0% of tests
Counts cover Major and Dangerous defects logged at test. Advisory items excluded so this shows why a car was rejected, not just what the tester flagged in passing.
Worst-case fix budget · top 3 failures
£128–£365
If every one of this Boxster's most-logged Major fails hit at the same MOT, that's the real-world UK garage range. Reality is usually one or two items, not all of them. Open the estimator →
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Tools that pre-empt a retest.
Picked against this car's top failure patterns. Affiliate links to Amazon UK — we earn a small cut at no cost to you. Disclosed up-front, doesn't shape the data.
Buying or keeping a Boxster?
Use the failure ranking as a pre-test checklist or a haggling lever. Treat the headline pass rate as a fleet-wide trend, not a guarantee on any individual car.
If you own a Boxster and your last MOT looked nothing like the ranked failures above, that's normal — individual cars vary widely. The ranking shows the patterns testers flag most often across the country.