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Porsche 928 s 4 vs Porsche Boxster: reliability comparison

MOT pass rates, common faults and mileage compared from real UK MOT data.

Porsche 928 s 4
67%
MOT pass rate · 1 vehicles
Porsche Boxster
83%
MOT pass rate · 46,488 vehicles
Verdict: On MOT pass rate the Porsche 928 s 4 (67%) and Porsche Boxster (83%) are very close — weigh the individual measures below, and remember condition depends on age, mileage and upkeep.

Head to head

Measure Porsche 928 s 4 Porsche Boxster
MOT pass rate 67% 83% ✓
MOT failure rate 33% 17% ✓
Faults & advisories per test 0.3 ✓ 1.4
Dangerous-fault share 0% ✓ 1%
Average mileage 19,533 mi 74,547 mi
Sample size (vehicles) 1 46,488

Most common faults

Porsche 928 s 4

  1. Rear Brakes imbalanced across an axle Axle 2 (1.2.1 (b) (i))

Porsche Boxster

  1. Nearside Rear Tyre worn close to the legal limit (4.1.E.1)
  2. Offside Rear Tyre worn close to the legal limit (4.1.E.1)
  3. Under-trays fitted obscuring some underside components
  4. Nearside Front Tyre worn close to the legal limit (4.1.E.1)
  5. Offside Front Tyre worn close to the legal limit (4.1.E.1)
  6. Nearside Rear Tyre worn close to legal limit/worn on edge (5.2.3 (e))

Reliability FAQ

On MOT pass rate the Porsche 928 s 4 (67%) and Porsche Boxster (83%) are very close — weigh the individual measures below, and remember condition depends on age, mileage and upkeep.

Full Porsche 928 s 4 report Full Porsche Boxster report Most reliable cars

Pass rates are computed over completed (pass/fail) MOT tests. Reliability also depends on age, mileage and upkeep — see each model's page for the full picture.