Porsche 924 MOT Failures

An analysis of 9,879 real DVSA MOT tests on the Porsche 924 — what fails, how often, and how that compares to every other car on UK roads. Generations covered: 924 (1976–1988).

Where the Porsche 924 fails its MOT

The single biggest MOT failure point on the Porsche 924 is wheel bearings worn — this model is 75 times more likely to fail on this item than the average car on UK roads. That makes it a major concern for anyone buying or owning this model. Across 9,879 MOT tests, 17.67% of all Porsche 924 tests recorded this as a failure.

Suspension failures typically mean worn bushes, drop links, or dampers. These affect handling and tyre wear. Budget £150–£400 per corner at an independent garage for full suspension overhaul.

Other notable weak points include brake hoses perished or damaged (86x the fleet average), vehicle structure corroded to the extent that t... (80x the fleet average), suspension component damaged or corroded (70x the fleet average), and windscreen washers not working or not providing... (29x the fleet average). These ratios compare the Porsche 924's failure rate on each item against the national average for all cars tested — a ratio of 10x means this model fails ten times more often than a typical car.

The failures span 6 categories: Suspension, Brakes, Bodywork, Wipers & Windscreen, Exhaust & Emissions and others. If you're inspecting a Porsche 924 before purchase, these are the areas to focus on — and if any have been flagged as advisories on a previous MOT, they're likely to become failures in the near future.

How failures change with mileage

The Porsche 924's weak points shift as the car covers more miles. Understanding these patterns helps you know what to expect — and what to budget for — at each stage of ownership.

Under 60,000 miles

At this mileage, most failures are either design-related or caused by age rather than wear. Components like bushes and drop links may not have been replaced yet, and original-fit parts can deteriorate even on low-mileage cars that spend a lot of time sitting.

For the Porsche 924 specifically, the DVSA data shows the most common failures at this mileage are emissions failure (756x the average) and excessive wear or play in a universal joint or ... (597x). electrical wiring fault (104x) and brake hoses perished or damaged (86x) also appear frequently.

60,000 to 100,000 miles

This is where routine wear items start to show up. Brake components, tyres, and exhaust parts have done serious work by this point. Cars that have been well serviced will show fewer of these failures — this mileage band is where good maintenance really separates the well-kept from the neglected.

For the Porsche 924 specifically, the DVSA data shows the most common failures at this mileage are emissions failure (256x the average) and excessive wear or play in a universal joint or ... (240x). wheel bearings worn (30x) and brake hoses perished or damaged (15x) also appear frequently.

Known issues beyond the MOT

An MOT only tests roadworthiness at a single point in time — it won't catch developing faults, intermittent problems, or issues that haven't yet reached the failure threshold. These are the issues that Porsche 924 specialists and owners flag most frequently, drawn from manufacturer technical bulletins, workshop data, and verified owner reports.

Wheel bearing premature failure Dangerous

MOT data shows 924 variants fail wheel bearing tests at 662.0 times the national average, with failures occurring across all mileage bands from 20k miles upward. Affects 924; typical independent garage repair cost is £150–£250.

Structural corrosion around suspension mounting points (924S) Dangerous

MOT data shows 924S variants fail structural integrity tests at 1652.1 times the national average between 40-80k miles for corrosion within prescribed areas around suspension mounting points. Affects 924; typical independent garage repair cost is £1,000–£3,000.

Emissions system failure causing MOT failure Major

The 924's emission control system includes a complex arrangement of vacuum-operated components, thermal reactors, and catalytic converters that degrade with age. Affects 924; typical independent garage repair cost is £400–£800.

CV joint wear and transaxle universal joint failure (924S) Major

The 924S uses a rear-mounted transaxle connected to the front engine by a long torque tube containing universal joints. Affects 924; typical independent garage repair cost is £1,500–£2,500.

For the complete picture — including repair costs across independent, specialist, and dealer garages — see the full Porsche 924 common problems breakdown.

What to check before buying a Porsche 924

Based on the MOT failure data and known issues above, here's what to prioritise when inspecting a Porsche 924:

Suspension — check for wheel bearings worn, suspension component damaged or corroded. Brakes — check for brake hoses perished or damaged, significant brake effort recorded with no brake.... Bodywork — check for vehicle structure corroded to the extent that t....

Beyond the MOT items, ask specifically about wheel bearing premature failure and structural corrosion around suspension mounting points. These won't show up on a standard MOT but can be expensive to fix — repairs start from £150. A specialist pre-purchase inspection is worth the investment on this model.

Always check the car's full MOT history for patterns — recurring advisories often become failures within 12 months. And verify the service history to confirm maintenance has been kept up to schedule. Enter any reg into our free car check to see the complete picture.

MOT failure data sourced from DVSA bulk test records via data.gov.uk. Ratios compare this model's failure rate against the national fleet average. Known issues sourced from manufacturer bulletins, specialist workshops, and verified owner reports.