Exhausts and Catalytic Converters
Book your free exhaust check at Kwik Fit
Engine noise? Low fuel efficiency? If you are at all concerned about the performance of your exhaust system or catalytic converter, or are experiencing loud or unusual noises coming from this area of your car, book an appointment online and our expert technicians will complete a free, no-obligation inspection of your vehicle.
At Kwik Fit, we stock exhausts to fit the widest selection of cars and light commercial vehicles, so when your exhaust fails you are never far away from the solution. And, with over 600 fitting centres across the UK, you are sure to find a Kwik Fit centre near you to help with your issue. Kwik Fit exhaust systems carry a 3-year guarantee – and when you purchase a complete system you could save even more money.
Please enter your vehicle registration below and click 'Search'.
Please note: we are currently unable to carry out exhaust checks on hybrid/electric vehicles.
You can also use this page to help you find answers to some common problems – from damaged exhaust pipes to unexpected exhaust gas.
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 moreA damaged or missing catalytic converter
While you might technically be able to stay on the road for a short while without a catalytic converter, it is illegal to do so and can dramatically impact the performance of your vehicle and even damage your engine. A car with a faulty CAT or without one altogether will make loud roaring noises and accelerate roughly.
If your car is showing signs of a faulty or missing catalytic converter, visit your nearest Kwik Fit as soon as possible. Our experts will be able to diagnose the issue and arrange a replacement.
Worried about the cost of a new catalytic converter? It would cost less than the potential implication of a failed MOT for excessive emissions! The exact cost of a new catalytic converter will vary depending on your car’s make and model, but is generally between £150 and £500 for most cars. For luxury models, a new CAT can cost more than that.
Exhaust systems
Exhaust systems are one of the most crucial components of your car, especially when it comes to starting up and pulling away. The exhaust system collects noxious gases like carbon monoxide and nitrogen oxide, generated by your engine, and removes the hazardous elements of these gases before safely distributing them out of the car and into the outside atmosphere.
If your car exhaust system fails, these dangerous fumes could enter the vehicle cabin, polluting the air that you and your passengers breathe. Failure of your exhaust system can also lead to the harmful elements of the fumes not being filtered out before being released into the atmosphere. A healthy car exhaust system, on the other hand, will reroute exhaust fumes, provide optimum fuel efficiency and improved engine performance, and help with noise control and quieter running.
So, if the exhaust starts encountering problems, it’s essential to check and diagnose the issue 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.
Common exhaust system issues
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
Is it safe to drive with an exhaust leak?
Exhaust leaks are not uncommon exhaust system problems and can be caused by rusting and damage to parts. You may have an exhaust leak if you notice noises, smells, reduced fuel economy, or loss of power.
If you ignore the signs of an exhaust leak, you run the risk of damaging engine components and polluting the environment. Most importantly, though, you could be exposed to toxic exhaust fumes in the cab of your vehicle. Because many of these emissions are odourless, overexposure to carbon monoxide - which can be deadly – is a possibility. All this to say, if you suspect an exhaust leak, get a mechanic to look at it ASAP!
How do I know if there’s something wrong 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, and that your exhaust may need replacing:
- Loud noises
- Reduced fuel efficiency
- Bad odours from exhaust
- Visible exhaust damage
- Check Engine light is on
- Sluggish car
We take a look at each of these in more depth below.
Loud noises coming from your exhaust
Loud noises are among some of the most obvious signs of a problem with your exhaust system. A faulty exhaust often sounds like roaring, hissing, chugging, or rattling noises - each of which may have their own specific cause within the exhaust system.
The silencer is the part of the exhaust that usually needs attention first, as it is the furthest away from the engine and is the most likely to be corroded by acidic moisture. This is because these parts remain relatively cold and give exhaust gases a chance to condense and form pools of corrosive acid inside the system. You'll know that you have a problem with your silencer because your exhaust starts making a loud roaring noise.
Other noises to listen out for include hissing, which indicates a crack in the exhaust manifold, exhaust pipe or a leaking gasket. A chugging noise could mean a blockage in the exhaust system.
If you hear rattling under the car it could mean that the exhaust system has become misaligned. If you can hear a loud metallic vibration, it usually means that something is touching the exhaust pipe or that a clamp, support bracket or mounting is loose. Hangers and brackets hold your exhaust in place. If these become corroded, fractured or fall off completely, it can cause extra stress to the exhaust housing which can also lead to premature exhaust failure.
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 - like a damaged or clogged exhaust pipe - 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.
Sometimes, the leak is in the exhaust pipe itself - otherwise, the culprit could be the exhaust manifold. This is the first section of the exhaust system responsible for funnelling exhaust gases towards the catalytic converter.
Visible exhaust damage
Examine the entire length of the exhaust from the engine all the way down to the exhaust pipe and look for any cracks or holes, especially where one section meets the next e.g. the seams and joins between the exhaust manifold and the cylinder. External rust may not be as serious as it first appears, because it may only be on the surface.
However, if the component has rusted through or is rusted from the inside (due to internal condensation build-up) it may be a cause for concern. Use a screwdriver to gently prod rusty areas; if the structural integrity feels weak or a hole is formed, it is a sure sign that this section of the exhaust needs to be replaced.
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 system 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 system 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.
Contact usExhausts 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 & MOTs3-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.