What does an exhaust manifold do?
The exhaust manifold is the first part of your vehicle’s exhaust system. It is bolted directly onto your car’s engine and collects your engine’s emissions. The exhaust manifold receives the air/fuel mixture from the multiple cylinders (either four, six or eight) in your vehicle’s engine and funnels them all into one pipe.
The exhaust manifold then completely burns any unused or incomplete burnt gases at a very high temperature. Finally once all the gases are in one place and completely burnt, the manifold sends the emissions into the rest of the exhaust system to eventually be expelled.
The exhaust manifold also performs another very important role. It houses an oxygen sensor which inspects the amount of oxygen entering the system. This data is then sent to the fuel injection system where the amount of oxygen used in the fuel/air mixture can increase or decrease.
How often should an exhaust manifold need replacing?
Due to the extreme temperature fluctuations inside the engine, the exhaust manifold is especially prone to wear, however it shouldn’t need to be replaced too often. We recommend having your entire exhaust system inspected every two to three years. If the manifold appears to be worn or damaged in any way, it should be replaced to ensure safe driving conditions.
Always look out for the above symptoms of a failing exhaust system, to ensure you get it fixed early and avoid any further, costly repairs.
What happens during an exhaust manifold replacement?
Our certified mechanics will:
Inspect the exhaust manifold.
If the exhaust manifold is visibly damaged or cracked, it will be replaced.
If necessary, they may also replace the exhaust gasket and clean the exhaust ports. The manifold's mounting bolts may also need to be replaced.
Advise if other related components need to be replaced.
They will then check for any leaks around the manifold and test drive the car.
What causes an exhaust manifold to break?
The exhaust manifold is exposed to extreme temperatures – it is constantly heating and cooling, which causes constant expansion and contraction. Despite being made of cast iron or stamped steel, over time manifolds can crack due to the stress from constant, extreme temperature changes.
When should an exhaust manifold be replaced?
Due to the extreme temperature fluctuations inside the engine, the exhaust manifold is especially prone to wear, however it shouldn’t need to be replaced too often. We recommend having your entire exhaust system inspected every two to three years. If the manifold appears to be worn or damaged in any way, it should be replaced to ensure safe driving conditions.
What are the symptoms of a bad exhaust manifold?
Usually, there a few signs you can look for:
A noisy engine exhaust
Burning smell coming from the engine
Decreased power, acceleration, and fuel efficiency
If the engine warning light comes on
When the engine makes more noise than usual
How often should you replace your exhaust manifold?
We recommend having your entire exhaust system inspected every two to three years. If the manifold appears to be worn or damaged in any way, it should be replaced to ensure safe driving conditions. Always look out for the above warning signs of a failing exhaust system, to ensure you get it fixed early and avoid any further, pricey repairs.
What happens during an exhaust manifold replacement?
Our certified mechanics will:
Inspect the exhaust manifold.
If the exhaust manifold is visibly damaged or cracked, it will be replaced.
If necessary, they may also replace the exhaust gasket and clean the exhaust ports. The manifold's mounting bolts may also need to be replaced.
Advise if other related components need to be replaced.
They will then check for any leaks around the manifold and test drive the car.
What is the average life of an exhaust manifold?
The lifespan of an exhaust manifold depends on the car, the driver and how often the car is used. In general, an exhaust manifold should last at least three years, but we recommend having your entire exhaust system inspected every two to three years. If the manifold appears to be worn or damaged in any way, it should be replaced to ensure safe driving conditions.
Can you drive with a broken exhaust manifold?
While you can technically drive with a broken exhaust manifold, it's neither safe nor legal and poses a number of issues when you're out on the road. Your exhaust plays a vital role in the healthy running of your car, therefore when the exhaust system experiences issues, it should be inspected as soon as possible.
Do exhaust manifolds deteriorate with age?
Yes exhaust manifolds are prone to wear and deterioration over time as they are constantly exposed to extreme temperatures. Despite being made of cast iron or stamped steel, over time manifolds can crack due to the stress from these constant, extreme temperature changes.
The law, vehicle regulations and your MOT
There are strict regulations regarding exhaust systems and car emissions. A car's exhaust system, including the manifold, cannot have any serious leaks, corrosion or cracks. An annual MOT tests both the exhaust system for leaks and deterioration and the emissions coming from the exhaust system.
