For 1990-2009 cars

1. Clean the manifolds in solvent.

Caution: Wear safety glasses in order to avoid eye damage.

2. Dry the components with compressed air.
3. Inspect the exhaust manifolds for the following:

• | Damage to the gasket sealing surfaces

• | Damage to the EGR pipe fitting (if applicable)

• | Damage to the take down studs

• | Restrictions within the exhaust passages

• | Broken or damaged heat shields (if applicable)

4. Measure the alignment or surface flatness of the exhaust manifold flanges using a straight edge and a feeler gauge. Refer to Engine Mechanical Specifications .

If the surface flatness is not within specifications, the exhaust manifold is warped and must be replaced.