MOT failure rates

Porsche 911 MOT failure rates: what to expect

What fails on a Porsche 911 at MOT, how often, and what each fix typically costs.

Updated 4th September 2026 DVSA data: Across 48,899 recorded MOT tests, 9.1% failed.

Porsche 911
Image via Wikipedia, CC-licensed.

The Porsche 911 is a celebrated sports car, but like any vehicle, it can face MOT failures. Common issues include worn brake components, suspension problems, and electrical faults. Fixing these can vary in cost, but being aware of them can help you prepare for your next MOT.

Brake System Failures

Brake components are crucial for safety and are often a reason for MOT failures on the Porsche 911. Common issues include worn brake pads, discs, and malfunctioning brake lines.

Additionally, if the brake discs are found to be warped or excessively worn, they will also need replacing. Regular checks and maintenance of the brake system can help prevent these issues from arising before the MOT.

Suspension and Steering Issues

Suspension and steering components are vital for handling and comfort, and they can often lead to MOT failures. Common problems include worn shock absorbers, damaged bushings, and misaligned wheels.

Worn bushings can lead to excessive play in the steering, affecting handling. Regular inspections of the suspension system can help identify these issues early, reducing the likelihood of MOT failures.

Electrical System Problems

The electrical system in the Porsche 911 is complex and can be a source of MOT failures. Common issues include faulty lights, malfunctioning indicators, and battery problems.

However, if the issue lies deeper within the electrical system, such as a failing battery or alternator, costs can rise significantly. Regular checks of the electrical system can help prevent unexpected failures during the MOT.

Exhaust and Emissions Failures

Emissions standards are strict in the UK, and the Porsche 911 must comply with these regulations. Common failures include exhaust leaks or a malfunctioning catalytic converter.

Keeping the exhaust system in good condition and addressing any issues promptly can help ensure compliance during the MOT.

Tyre Condition and Tread Depth

Tyres are a critical safety component and are frequently checked during the MOT. Common issues include insufficient tread depth and uneven wear. The legal minimum tread depth in the UK is 1.6mm, and if tyres are found to be below this limit, they will need replacing.

Additionally, uneven wear may indicate alignment or suspension issues that need addressing. Regular tyre rotations and checks can help prolong tyre life and ensure compliance during the MOT.

Bodywork and Structural Integrity

While not as common, bodywork and structural integrity can also lead to MOT failures. Issues such as rust, corrosion, or damage to the chassis can be problematic.

Structural issues can be more serious and may require professional assessment. Repairing structural damage can be costly and may involve extensive work. Regular inspections of the bodywork can help catch these issues early, preventing them from becoming major problems during the MOT.

Understanding these common MOT failures and their associated costs can help Porsche 911 owners prepare effectively. Regular maintenance and timely repairs can significantly reduce the risk of MOT failures, ensuring your vehicle remains in top condition.

Porsche 911 recall record

37 recalls have been issued for the Porsche 911, between 1992 and 2025.

  1. ASA0 - Check rear seat belt buckles and rework if necessary

    R/2025/077

    Issued 26 February 2025

    Due to a process error in the production an aluminium butyl may have been positioned incorrectly and the screw connection of the rear left and right belt buckle was potentially not executed according to the specifications. If this is the case the correct fastening of the belt buckle cannot be guaranteed. The loosening of the rear belt buckles in the event of an accident or emergency braking cannot be ruled out. This could increase the associated risk of injury.

    Remedy:The positioning of the aluminium butyl mat on the left and right of the affected vehicles must be checked and depending on the test result the screw connection must be reworked.

    Affects cars built Feb 2023 to Sept 2023

  2. ARC4 Stop Use & Safety Recall - Wheel attachment with central locking

    R/2024/427

    Issued 28 October 2024

    On affected vehicles the wheel attachments using the central lock may not meet the required specifications. This can lead to damage / breakage and the possibility of wheel detachment.

    Remedy:Check the correct functioning of the central lock wheel fastening system and replace if necessary.

    Affects cars built Sept 2023 to Oct 2024

  3. ARA3 - Check front and rear windows and replace if necessary

    R/2024/140

    Issued 13 March 2024

    On the affected vehicles it is possible that the front and rear window panes were not manufactured in accordance with specifications and their bonding to the body is therefore insufficient

    Remedy:To prevent this from happening the front and rear windows on the affected vehicles must be checked and if necessary replaced

    Affects cars built Jul 2020 to Feb 2024

  4. On affected vehicles the side airbag installed in bucket seats may be activated unnecessarily.

    R/2023/319

    Issued 8 November 2023

    On affected vehicles the side airbag installed in bucket seats may be activated unnecessarily.

    Remedy:Recode the airbag control unit

    Affects cars built Mar 2021 to Oct 2023

33 older recalls not shown.

A recall applies to a build range, not to every car of this model. Check a registration to see whether one specific vehicle has an outstanding recall.

Porsche 911 MOT record

From 48,899 recorded MOT tests, 9.1% failed.

MOT pass and failure rates by year of first registration
RegisteredTestsFailedMedian mileage
20222,4633.6%8,852 mi
20211,6462.5%12,540 mi
20201,4673.7%18,521 mi
20192,2444.5%21,496 mi
20182,0744.7%19,409 mi
20171,8475.4%26,045 mi
20161,6764.9%30,349 mi
20151,7144.9%32,938 mi

Most common reasons for failure

  1. Tyre tread depth not in accordance with the requirements26.5%
  2. Brake pipe damaged or excessively corroded22.7%
  3. A tyre seriously damaged21.7%
  4. A suspension pin, bush or joint excessively worn14.7%
  5. Brake disc or drum excessively weakened, insecure or fractured14.5%

Figures cover every Porsche 911 tested in the DVSA dataset, not this specific car. Check a registration for the actual history of one vehicle.

Porsche 911 official figures

Median across 20 variants on sale, petrol, petrol electric.

Combined economy
25.9 mpg
WLTP median across variants
CO2 emissions
247 g/km
Sets the first-year tax rate

Official figures for new cars. Real economy varies with driving, load and conditions.

Frequently asked questions

What is the MOT requirement for a Porsche 911 in the UK?

In the UK, a Porsche 911 must have an MOT test when it is three years old and then annually thereafter. This ensures that the vehicle meets safety and environmental standards.

How can I check the MOT history of a Porsche 911?

You can check the MOT history of a Porsche 911 by visiting the official UK government website. You will need the vehicle's registration number to access its MOT records.

What common issues might a Porsche 911 face during its MOT?

Common issues that may arise during an MOT for a Porsche 911 include worn brake pads, faulty lights, and issues with emissions. Regular maintenance can help prevent these problems.

What should I do if my Porsche 911 fails its MOT?

If your Porsche 911 fails its MOT, you will receive a list of reasons for the failure. You will need to address these issues and have the vehicle retested before it can be legally driven.

Can I drive my Porsche 911 if the MOT has expired?

You cannot legally drive your Porsche 911 if the MOT has expired, unless you are driving it to a pre-booked MOT appointment. It is important to ensure your vehicle is roadworthy.

How can I prepare my Porsche 911 for its MOT?

To prepare your Porsche 911 for its MOT, check the lights, brakes, and tyres, and ensure all fluids are topped up. A thorough inspection can help identify any issues before the test.

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