Porsche 928 S (1990)

149 real MOT outcomes analysed • 76.7% first-time pass rate

1990 Porsche 928 S

CarHunch analysed 149 real MOT records for the 1990 Porsche 928 S. This breakdown of actual test outcomes — pass rates, defect profiles, mileage data — isn't published anywhere else.

The 1990 Porsche 928 S falls slightly below the UK average with a 76.7% first-time pass rate, and one in five of these cars (21.5%) have been flagged with dangerous defects during MOT testing—a genuine concern for a buyer. With an average of 2.7 failures per test, these are cars that demand proper maintenance and aren't forgiving of neglect.

At 112,944 miles median, these 928 S examples are showing typical wear for their age, but the real issue is the advisory count: averaging 11.7 per test suggests widespread minor issues and degradation across multiple systems. Before buying, have a pre-purchase inspection focus on cooling (these engines run hot), fuel system integrity, and electrical gremlins—then budget for the repair bills that come with a complex 1980s supercar.

Average reliability 3.3% below UK average
76.7%
pass MOT first time
UK average: ~80%
112,944
typical mileage
89,083–130,565 middle half
21.5%
ever had a dangerous defect
recorded at any MOT
2.7
avg MOT failures per car
over 11.2 tests on record

What to check before buying a 1990 Porsche 928 S

Practical pre-purchase checks for this age and model.

  • 📋 Check the full MOT history. Look for recurring advisories — slow-building issues like corrosion or brake wear patterns show up years before they become failures. Enter the reg below for a full AI analysis.
  • 🔍 Inspect for corrosion in person. Brake pipes, sills, subframes, and chassis legs. Surface rust is normal at this age; structural rust is a serious problem that's expensive to fix and can fail an MOT.
  • 🛞 Check tyres and brakes. The most common advisory items at this age. Budget for replacement if they're near the limit — factor this into your offer price.
  • ⚠️ 21.5% of these vehicles have had a dangerous defect recorded. Enter the reg below — the full MOT history will show exactly what was flagged and whether it was resolved.
  • 📄 Run an HPI check. The MOT history won't show outstanding finance, insurance write-offs, or stolen status — an HPI check will.

Before you buy a Porsche 928 S

MOT history is one piece of the puzzle. These checks can reveal what CarHunch can't.

Inspection ClickMechanic Have a qualified mechanic check this car before you commit to buying

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Pass Rate by Fuel Type

Fuel type Vehicles Pass rate Avg failures
Petrol (99%) 148 76.7% 2.71
Other (1%) 1 87.5% 1

Mileage Distribution

Most 1990 Porsche 928 S vehicles sit in the blue band. If the car you're looking at is outside it, it's either unusually low or high mileage for its age.

89,083
low mileage
112,944
typical
130,565
high mileage

Half of all 1990 Porsche 928 S vehicles fall between 89,083 and 130,565 miles.

1990 Porsche 928 S — Still on the Road

40 vehicles still getting MOTs in 2025 — 62% of the peak remain.

55 40 2014 2025

Based on vehicles from this manufacture year that had at least one MOT test in each calendar year. Data from 2014–2025.

MOT History Averages

11.2
Avg MOT tests per vehicle
2.7
Avg failures per vehicle
11.7
Avg advisories per vehicle

Found a specific Porsche 928 S?

Enter the reg to see its individual MOT history, AI Hunches, and how it compares to this cohort.

UK

Other model years — Porsche 928 S:

1980 1981 1982 1983 1984 1985 1986 1987 1988 1989 1991