MG Zr MOT Failures
An analysis of 48,029 real DVSA MOT tests on the MG Zr — what fails, how often, and how that compares to every other car on UK roads. Generations covered: ZR (2001–2005).
Where the MG Zr fails its MOT
The single biggest MOT failure point on the MG Zr is power steering fault — this model is 188 times more likely to fail on this item than the average car on UK roads. That makes it an extreme outlier for anyone buying or owning this model. Across 48,029 MOT tests, 6.62% of all MG Zr tests recorded this as a failure.
Steering faults include worn track rod ends, power steering leaks, and rack wear. These are safety-critical — any play in the steering should be investigated immediately.
Other notable weak points include electrical wiring fault (28x the fleet average), exhaust system damage (31x the fleet average), structural corrosion (64x the fleet average), and abs fault (34x the fleet average). These ratios compare the MG Zr'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: Steering, Lights & Electrics, Bodywork, Suspension, Exhaust & Emissions and others. If you're inspecting a MG Zr 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 MG Zr'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 MG Zr specifically, the DVSA data shows the most common failures at this mileage are power steering fault (188x the average) and structural corrosion (64x). transmission shaft constant velocity joint boot... (31x) and exhaust system damage (29x) 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 MG Zr specifically, the DVSA data shows the most common failures at this mileage are power steering fault (65x the average) and electrical wiring fault (28x). exhaust system damage (26x) and fluid leak (17x) also appear frequently.
Over 100,000 miles
High-mileage cars accumulate failures across multiple systems. The key question isn't whether things will need doing — they will — but whether the car has been maintained well enough to keep on top of them. Look for a consistent service history and recent MOT passes with minimal advisories.
For the MG Zr specifically, the DVSA data shows the most common failures at this mileage are electrical wiring fault (26x the average) and exhaust system damage (22x). emissions failure (22x) and power steering fault (17x) also appear frequently.
The shift from power steering fault at lower mileages to electrical wiring fault at higher mileages is typical — early failures tend to be design or factory-related, while high-mileage failures reflect accumulated mechanical wear. A car that's been well maintained will usually dodge the worst of both.
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 MG Zr specialists and owners flag most frequently, drawn from manufacturer technical bulletins, workshop data, and verified owner reports.
Structural corrosion compromising rigidity Dangerous
The ZR suffers from severe structural corrosion that compromises the rigidity of the body assembly. Affects ZR; typical independent garage repair cost is £800–£2,500.
Subframe area corrosion Dangerous
The ZR suffers from severe corrosion in prescribed areas within 30cm of subframe, spring, and suspension component mounting points. Affects ZR; typical independent garage repair cost is £600–£1,500.
Power steering system failure Major
The ZR suffers from widespread power steering system failures affecting both fluid leaks and pump malfunction. Affects ZR; typical independent garage repair cost is £250–£450.
Head gasket failure (K-Series engines) Major
The K-Series engines in the ZR are notorious for head gasket failure due to the wet liner design and inadequate head bolt clamping. Affects ZR; typical independent garage repair cost is £800–£1,500.
For the complete picture — including repair costs across independent, specialist, and dealer garages — see the full MG Zr common problems breakdown.
What to check before buying a MG Zr
Based on the MOT failure data and known issues above, here's what to prioritise when inspecting a MG Zr:
Steering — check for power steering fault. Lights & Electrics — check for electrical wiring fault. Bodywork — check for exhaust system damage, structural corrosion.
Beyond the MOT items, ask specifically about structural corrosion compromising rigidity and subframe area corrosion. These won't show up on a standard MOT but can be expensive to fix — repairs start from £800. 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.
Looking at a specific MG Zr?
Enter the reg to see its full MOT history, mileage records, write-off status, and finance checks.
MG Zr MOT FAQs
What are the most common MOT failures on a MG Zr?
Based on 48,029 DVSA MOT tests, the most common failure is power steering fault — at 188x the national fleet average. Other frequent failures include electrical wiring fault and exhaust system damage.
Is the MG Zr reliable based on MOT data?
The MG Zr has 15 MOT failure categories above the fleet average. Specialists also flag structural corrosion compromising rigidity as a concern. A pre-purchase inspection and service history check are recommended.
What MOT failures should I expect at high mileage?
Above 100,000 miles, the MG Zr most commonly fails on electrical wiring fault and exhaust system damage. Under 60,000 miles, the main issues are power steering fault and structural corrosion.
How do I check a MG Zr's MOT history?
Enter the registration number into our free car check above. You'll see every MOT test result, advisories and failures, mileage readings, write-off status, and finance checks.
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.