What is the Exhaust Manifold all about?

Depending on your engine and type of vehicle, the exhaust manifold can either be a set of pipes or it can be a cast iron manifold assembly. Essentially the exhaust manifold takes the burned exhaust gases from the engine’s cylinders and ejects the gas through the exhaust system and out through the car's tail pipe. The exhaust gases are the burned fuel/air residue from the combustion process in the cylinders of the engine. Over time, the constant expansion and contraction of the components (caused by constant heating and cooling in the engine), may cause the manifold to crack and leak. These leaks can be hazardous as hot exhaust gases escape and can damage other components in the engine compartment. A leaky exhaust manifold can also impact engine performance.

Keep in mind:

Sometimes an exhaust manifold starts to leak because a mounting bolt has broken. If this happens, the mechanic will have to remove the broken bolt or stud, which can increase the labor time needed to fix the problem. Your mechanic may charge you an additional fee, depending on the severity of the situation.

How it's done:

• Determine if the manifold is cracked or broken.
• Remove and replace faulty exhaust manifold.
• Inspect exhaust studs, clean carbon and old gasket off cylinder head.
• Install new gasket and exhaust manifold.
• Start engine and check for exhaust leaks.

Our recommendation:

The exhaust manifold is transferring burned gasses from the engine. It is located in a high temperature zone, and it will leak eventually. There is no way to prevent it. Your mechanic should use anti-seize compound on the bolts when they are replacing this part. This will help prevent bolts from breaking in the cylinder head.

What common symptoms indicate you may need to replace the Exhaust Manifold?

• Loud noise from engine.
• Lack of engine performance.
• Check engine light is on.
• Smells from the engine compartment (eg. plastic components next to exhaust manifold melting from escaped heat).

How important is this service?

A leaky exhaust manifold is a health and safety concern. Hot exhaust gases escaping from the engine can be a fire hazard melting nearby plastic components in the engine compartment.