Common issues with your car exhaust system

Your car exhaust system plays an essential role in keeping you safe on the roads by carrying harmful gases away from the driver and passengers and converting them into less damaging gases before they are released. It also enhances engine performance and improves fuel economy.

Car exhaust problems are reasonably common and can have various consequences if left alone, including risks to your health and safety, negative environmental impacts and expensive repairs. A faulty exhaust will also cause an automatic MOT failure, so ensuring it’s in good condition is essential for keeping your vehicle roadworthy.

Our comprehensive guide will take you through the most common issues with car exhausts, how they can be identified and what to do about them.

What are the most common issues with car exhaust systems?

Most drivers will have experienced some kind of problem with an exhaust system in their time on the road. Fortunately, car exhaust problems tend to be pretty easy to spot, as they’re usually accompanied by a loud noise or strange smell.

Let’s explore some of the most common car exhaust problems and break down how they can be identified.

Exhaust leaks

Exhaust leaks happen when harmful gases from inside your exhaust system leak out before they reach the tailpipe. A leaking exhaust can be extremely dangerous, as it impedes your exhaust system’s ability to remove fumes, potentially exposing you to harmful gases like carbon monoxide. An exhaust leak also negatively impacts the overall engine performance of your car and worsens its impact on the environment.

Exhaust leaks are common and can occur over time. Your exhaust system is exposed to extreme temperatures when you turn a vehicle on and off, gradually causing leaks or holes in your exhaust to develop.

There are numerous signs that your car has an exhaust leak, including:

• Gas smell 
•  Increasingly loud engine noise 
• Poor fuel economy 
• Loss of accelerating power

If you experience any of these symptoms, you should take your car to be examined and repaired by a professional as soon as possible. You can arrange an appointment with your local ATS centre for exhaust system repairs and replacement services carried out by our expert technicians.

Rust 

Perhaps the most common cause of exhaust system problems is rust. While a car is running, the exhaust system is exposed to heat and water vapour, which can cause parts of your exhaust to rust over time. This may be particularly prevalent in cars that are used mostly for short journeys, as the exhaust doesn’t get hot enough to fully burn off the water vapour.

Once you start to develop rust, it spreads quickly and can lead to major problems such as cracks or holes in your exhaust system. A rusty exhaust can be identified by a quick visual inspection. If the rust has developed and is impacting the exhaust silencer (or muffler), it may cause a loud, roaring noise. Any exhaust parts that are rusted should be replaced.

Rust, as well as general wear and tear, can also cause parts of your exhaust system to become loose or misaligned. If you hear a metal rattling noise from your exhaust or under the car, it usually signals a loose part that’s rubbing against something it shouldn’t be. 

Catalytic converter failure

The catalytic converter does the important job of converting dangerous gases into less damaging ones. If it fails, the vehicle can produce dangerous emissions that are bad for your health and the environment, as well as potentially causing an emissions test failure. A failing catalytic converter can also cause engine misfires, making it difficult to start your car.

If your catalytic converter is failing or faulty, you are likely to notice various symptoms, including: 

• Poor engine performance
• Reduced acceleration or difficulty starting your car
• Rotten egg smell
• Dark exhaust smoke

If you do spot any of these, you should take your vehicle to an expert for an exhaust system examination and any necessary repairs or replacements.

Oxygen sensor failure

Another important component in your car exhaust system is the oxygen sensors, whose job it is to detect the levels of oxygen in your vehicle. These oxygen readings are used to create a balanced air-to-fuel ratio to provide maximum efficiency. 

Most cars have numerous oxygen sensors, but a failure in a single one of them can cause exhaust problems, as the system is unable to fully regulate the air-fuel balance. If any of your oxygen sensors are failing, your engine is likely to misfire, causing symptoms such as loss of accelerating power and stalling.

Blockages 

Blockages or clogs in an exhaust system are quite common. They can be caused by debris or soot getting into the exhaust pipe or a build-up of carbon in the catalytic converter. Usually, the exhaust system will be able to expel any minor blockages by itself, but larger clogs can cause problems.

A major blockage will cause the engine to work harder to push out the exhaust, which leads to reduced efficiency and poor fuel economy. A clogged exhaust system tends to be harder to spot than other exhaust problems, but you’ll usually notice chugging or clanging noises, more sluggish engine performance and increased fuel consumption.

Exhaust system repairs and replacements 

These are a few of the most common causes of car exhaust system problems, each of which can cause risks to your safety, as well as cause damage to your vehicle and the environment.

If you experience any of the symptoms listed above, you should always take your car to be examined by a professional as soon as possible. At ATS, we offer exhaust system checks, where our qualified technicians can examine your car exhaust and advise on any necessary repairs or new exhaust system replacements. Our exhaust services are available at over 150 centres across the UK, so find your local ATS centre and book an appointment today.