Exhausts and Catalytic Converters

Book your free exhaust check at Kwik Fit

Engine noise? Low fuel efficiency? If you are concerned about the performance of your exhaust system or catalytic converter, please book an appointment online and our expert technicians will complete a free, no-obligation inspection of your vehicle.

Please enter your vehicle registration below and click 'Search'.

Please note: we are currently unable to carry out exhaust checks on hybrid/electric vehicles.

What is a catalytic converter?

A catalytic converter or 'CAT' forms part of the exhaust system of a car and reduces harmful emissions of hydrocarbons, carbon monoxide, and nitrogen oxides escaping into the atmosphere.

These pieces of exhaust equipment are located underneath your vehicle and are essential for keeping your car running clean. However, they are susceptible to damage. Catalytic converters can clog, overheat, age, and even encounter physical damage from driving over bumps; so, it is essential to make sure your catalytic converter stays healthy.

Find out more

Exhaust systems

Exhaust systems are one of the most crucial components of your car, especially when it comes to starting up and pulling away. So, if the exhaust starts encountering problems, it’s essential to check and diagnose the issues as soon as possible.

Vehicles used for short trips around town tend to experience exhaust corrosion in a much shorter period of time and distance than cars used predominantly for long journeys.

The most common problems associated with exhaust systems and catalytic converters are as follows:

  • Cracked or leaking exhaust pipes
  • Failing or damaged oxygen sensors
  • Clogged or faulty catalytic converter
  • Rust or corrosion damage
  • A hole in your exhaust or tailpipe
  • Loose or broken exhaust mounts

Find out more in our blog 'Common Exhaust Problems & How to Spot Them'.

How can I tell if there's a problem with my exhaust?

The following signs are all potential indicators that your car is encountering any one (or a combination) of the exhaust system problems mentioned above:

Loud noises coming from your exhaust

A loud rumbling sound coming from your exhaust can indicate a hole or leak in the exhaust system. This is usually to do with damage to the silencer. The silencer forces the sound waves produced by the engine out through the exhaust. If the exhaust becomes corroded or there is a hole in the silencer, the sound waves are no longer muffled and the exhaust will become very noisy.

Reduced fuel efficiency

If you're noticing that your car seems to be much thirstier than usual, and you see a decrease in miles per gallon, it could be related to an exhaust system issue affecting engine performance.

Bad odours coming from your exhaust

A strong smell of gases inside the car can indicate a leak in the exhaust system, potentially exposing you to harmful emissions. Usually, this smells like rotten egg or sulphur and you might even be able to smell it in the cabin.

Visible exhaust damage

Take a look at your exhaust pipe. Can you see any discoloured sections of the exhaust or flaking areas? Any visible signs of rust or damage to the exhaust components can lead to leaks and decreased performance.

Check Engine light for exhaust issues

The Check Engine light can come on for various reasons, including issues with the exhaust system sensors or emissions levels. As such, there may well be an exhaust-related problem at play if this light comes on.

Sluggish car

If you notice that your car feels sluggish and doesn't accelerate like it used to, it might be down to an exhaust system problem causing power issues.

What happens if my exhaust fails?

Exhausts can corrode from both the inside and outside. How long your exhaust lasts depends on how far and how often you drive your car rather than the length of time it has been fitted.

An exhaust that has failed can lead to noxious fumes being drawn into the vehicle cabin and prolonged exposure to exhaust fumes can make a vehicle occupant feel drowsy, which could lead to an even greater danger. So, it’s important to maintain a healthy exhaust system.

If you hear any strange noises at all coming from your exhaust such as rattling or excessive roaring, you should take your vehicle to your nearest Kwik Fit centre as soon as possible. Our qualified exhaust specialists will then be able to examine the exhaust and help diagnose the fault.

Exhaust repairs at Kwik Fit

Should our technicians diagnose a problem with your exhaust that requires a replacement, you then have the option to replace the whole exhaust or just parts of it. Often, if one area of the exhaust or tailpipe is corroded, it is likely that other parts of a similar age could be corroded too. Sometimes. the different elements of an exhaust fuse together because of a build-up of heat and they are starting to corrode. This can make the separation of the individual components extremely difficult.

But, if they haven't fused, it's a matter of judgement and consideration based on vehicle usage, driving habits, and distances travelled as to whether individual exhaust parts should be replaced or the entire exhaust assembly. Sometimes, it can save you time and money in the long run to replace more than the corroded part.

Keep up with exhaust system maintenance

For best practice, and to keep your vehicle in ideal condition, Kwik Fit recommends you have your car’s exhaust system checked at least twice a year for cracks, leaking joints, broken hangers, worn rubber mountings, corrosion, failed gaskets, and other damage or wear.

After we have completed your inspection, we will provide you with a written report and a quote for any work which is required.

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Exhausts and the law

Under existing regulations, a police officer can warrant the removal of any vehicle from the roadways on the suspicion that it is producing excessive amounts of pollutant gases from the exhaust. Also, if your vehicle exhaust system is broken and noisy, your vehicle is more likely to fall under police scrutiny. So, it’s better to keep your exhaust in check than run the risk of a nasty encounter with police.

Exhaust systems & MOTs

The MOT in the UK now assesses exhaust systems, too. So, your vehicle may fail its MOT test if its exhaust system has a fault resulting in incorrect emissions levels being recorded. This may be down to a leak, a hole, a malfunctioning catalytic converter or even rust and corrosion. If your exhaust is producing emissions that exceed legal limits — for whatever reason — this can be enough to warrant an MOT failure which is not only frustrating but costly too. If in doubt, get it checked out.

More on exhausts & MOTs

3-year guarantee

We want to help you maintain a healthy exhaust system so don't leave it until your next MOT test or vehicle service; book a free inspection without obligation. All Kwik Fit exhausts come with a 3 year guarantee.

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