Ford Fiesta MOT Failures
An analysis of 1,042,679 real DVSA MOT tests on the Ford Fiesta — what fails, how often, and how that compares to every other car on UK roads. Generations covered: Mk7 (2008–2019), Mk8 (2017–2023), Mk6 (2008–2017).
Where the Ford Fiesta fails its MOT
The single biggest MOT failure point on the Ford Fiesta is emissions failure — this model is 489 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 1,042,679 MOT tests, 0.35% of all Ford Fiesta tests recorded this as a failure.
Exhaust and emissions failures often point to catalytic converter degradation, lambda sensor faults, or — in diesel models — DPF problems. These can be expensive to fix and will cause an immediate MOT failure.
Other notable weak points include braking effort inadequate at a wheel (96x the fleet average), brake hoses perished or damaged (110x the fleet average), seat mounting fault (84x the fleet average), and sharp bodywork damage (81x the fleet average). These ratios compare the Ford Fiesta'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 5 categories: Exhaust & Emissions, Brakes, Seatbelts & Airbags, Bodywork, Suspension. If you're inspecting a Ford Fiesta 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 Ford Fiesta'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 Ford Fiesta specifically, the DVSA data shows the most common failures at this mileage are emissions failure (193x the average) and abs fault (129x). light unit fault (119x) and brake hoses perished or damaged (84x) 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 Ford Fiesta specifically, the DVSA data shows the most common failures at this mileage are emissions failure (239x the average) and suspension ball joints worn (93x). lamp emitted colour, position or intensity not ... (43x) and service brake efficiency below minimum requirement (38x) 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 Ford Fiesta specifically, the DVSA data shows the most common failures at this mileage are airbag fault (62x the average) and emissions failure (38x). power steering fault (28x) and floor deteriorated or insecure (28x) also appear frequently.
The shift from emissions failure at lower mileages to airbag 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 Ford Fiesta specialists and owners flag most frequently, drawn from manufacturer technical bulletins, workshop data, and verified owner reports.
Cylinder head cracking (fire risk) (Mk7) Dangerous
1.6 EcoBoost ST models built between 2 June 2010 and 20 December 2014 suffer from cylinder head cracking that allows engine oil to leak onto the hot exhaust manifold, creating a significant fire risk. Affects Mk7; typical independent garage repair cost is £1,500–£2,500.
Head gasket failure (Mk8) Dangerous
Early production 1.5 EcoBoost engines suffer premature head gasket failure due to inadequate cylinder head bolt torque specification and thermal cycling stress. Affects Mk8; typical independent garage repair cost is £1,200–£2,000.
Coolant system failure (nylon pipe) (Mk7) Dangerous
Early 1.0 EcoBoost engines (2012-2016) used nylon coolant pipes that become brittle and fail suddenly, causing complete coolant loss and immediate overheating. Affects Mk7; typical independent garage repair cost is £200–£2,500.
Powershift automatic transmission failure (Mk7) Dangerous
The dual-clutch Powershift automatic transmission fitted to 2011-2015 Fiestas has a catastrophic failure rate due to premature clutch wear and control module faults. Affects Mk7; typical independent garage repair cost is £1,500–£3,000.
For the complete picture — including repair costs across independent, specialist, and dealer garages — see the full Ford Fiesta common problems breakdown.
What to check before buying a Ford Fiesta
Based on the MOT failure data and known issues above, here's what to prioritise when inspecting a Ford Fiesta:
Exhaust & Emissions — check for emissions failure. Brakes — check for braking effort inadequate at a wheel, brake hoses perished or damaged, service brake efficiency below minimum requirement. Seatbelts & Airbags — check for seat mounting fault.
Beyond the MOT items, ask specifically about cylinder head cracking and head gasket failure. These won't show up on a standard MOT but can be expensive to fix — repairs start from £1,500. 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 Ford Fiesta?
Enter the reg to see its full MOT history, mileage records, write-off status, and finance checks.
Ford Fiesta MOT FAQs
What are the most common MOT failures on a Ford Fiesta?
Based on 1,042,679 DVSA MOT tests, the most common failure is emissions failure — at 489x the national fleet average. Other frequent failures include braking effort inadequate at a wheel and brake hoses perished or damaged.
Is the Ford Fiesta reliable based on MOT data?
The Ford Fiesta has 24 MOT failure categories above the fleet average. Specialists also flag cylinder head cracking 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 Ford Fiesta most commonly fails on airbag fault and emissions failure. Under 60,000 miles, the main issues are emissions failure and abs fault.
How do I check a Ford Fiesta'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.