Common exhaust issues and how to spot them

Your car exhaust emissions system is crucial for your car to operate safely. 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, causing damage to your health. 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, exposing the surrounding air and those breathing it to these gases.

Unsurprisingly, current regulations state that the Police can warrant the removal of any vehicle from the roads on the suspicion that it is producing excessive amounts of pollutant gases from the exhaust.

A healthy car exhaust system, alongside rerouting engine fumes, will also provide:

• optimum fuel efficiency
• improved engine performance
• noise control and quieter running

As a result, it is important to ensure your exhaust is working to the best of its ability. Identifying a problem with your exhaust system is fairly easy, and the only tools you’ll need to find out if you need an exhaust repair or replacement are your sight and hearing!

How to spot an exhaust problem

Many car exhaust problems can be identified with a visual check. You can spot various types of damage from cracks to rust and corrosion.

For holes and cracks, examine the entire length of the exhaust starting at the engine and continue down to the tailpipe, keeping a lookout for damage, especially the seams and joints where the different sections meet.

For rust and corrosion, you’ll be able to see external rust immediately. However, it isn’t always as serious as it first appears, as 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 you’ll need an exhaust replacement, at least for this section,

If your car is used mostly for short trips, it’s more likely for your car exhaust system to experience corrosion because the exhaust system doesn’t reach the temperature needed to burn off accumulated water on these shorter trips.

Listen for the signs

Listen out for unusual sounds coming from your exhaust system. A noisy exhaust or an exhaust that is making strange sounds is a sure way to detect a problem as well as indicate potential damage.

The silencer is the part of the exhaust that usually needs attention first due to its tendency to become corroded by acidic moisture. If you have a problem with your silencer, you’ll be able to hear it as your exhaust will begin to make a loud roaring noise.

Other noises to listen out for include hissing, chugging, loud metallic vibrations and rattling, with each of these noises being linked to a different issue. Hissing noises typically indicate a crack in the exhaust manifold, exhaust pipe or a leaking gasket, while the presence of a chugging noise coming from your exhaust 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. A loud metallic vibration usually means that something is touching the exhaust pipe or that a clamp, support bracket or mounting, which hold your exhaust in place, is loose. Corroded, fractured or missing brackets and hangers can cause extra stress on the system which can also lead to premature exhaust failure, resulting in needing an exhaust replacement.

Your exhaust might not be the problem

Should your exhaust begin to produce smoke, this typically isn’t a sign of a problem with the exhaust but rather an issue with the engine.

Black exhaust smoke means that your engine is burning fuel too quickly, if this occurs check your air filter, fuel injectors and the fuel pressure regulator. On the other hand, if you see white smoke coming from the exhaust, it may be nothing to worry about as it could simply be a build-up of condensation in the exhaust system.

However, if the exhaust continuously emits white smoke, this suggests your engine is burning coolant and you may have a problem with your cylinder head or have a cracked head gasket. You’ll be able to spot if coolant is leaking into your engine oil as it will appear discoloured and creamy.

If in doubt we’ll check it for free

Don’t risk failing your MOT, or worse still, putting your health at risk. If you have any concerns regarding the health of your car exhaust system, our trained technicians can provide a free exhaust and emissions check at over 600 centres across the UK.

We’ll check your exhaust and catalytic converter for a variety of damages such as cracks, leaking joints, broken hangers, worn rubber mountings, corrosion, failed gaskets and high levels of pollutant gasses.

Once our checks are completed, we’ll be happy to discuss and provide guidance on any areas that do not meet safety requirements. Book online for our free no obligation exhaust inspection service, or contact your local KwikFit centre.