Intake and Exhaust Gaskets
Intake and exhaust gaskets seal the manifolds to the cylinder head, keeping unmetered air out of the intake and exhaust gas inside the exhaust system.
What it does
The intake gasket maintains a sealed path for metered air. The exhaust gasket must hold a gas-tight seal under extreme heat cycling and vibration.
Signs a manifold gasket is failing
- A ticking or blowing noise from the manifold area, loudest on cold start
- Rough idle or a lean running fault code, from an intake leak
- A smell of exhaust gas in the engine bay or cabin
- Soot deposits around the manifold joint
When to replace them
Not scheduled. Replaced whenever a manifold is removed, and when a leak develops.
What to confirm before ordering
Have these ready and the counter can usually confirm the part in under a minute.
- Engine code from the block
- Intake or exhaust, since they are different materials
- Whether the manifold studs and nuts should be replaced, as they corrode badly
- Whether the manifold face needs checking for flatness
Intake and Exhaust Gaskets questions
What does an exhaust manifold leak sound like?
A rhythmic ticking or puffing that is loudest on cold start and often quietens as the metal expands and partially closes the gap. It usually rises with engine speed.
Can an intake leak cause a fault code?
Yes. Air entering after the airflow sensor is unmetered, so the mixture runs lean and the ECU logs a lean running or fuel trim fault.