Exhaust Manifold Cleaning and Inspection

WARNING: This page is about a different car, the 2006 GMC Yukon XL, 2006 Chevrolet Suburban, and 2006 Chevrolet Avalanche. However, it is still accessible from the selected car via links, so may be relevant.

Fig 1: View Of Left Exhaust Manifold, Gasket, Bolts And Nuts

Courtesy of GENERAL MOTORS CORP.

Clean the exhaust manifolds in solvent.

CAUTION: Refer to Safety Glasses Caution in Cautions and Notices.

Dry the components with compressed air.
Inspect the exhaust manifolds for the following:
- Damage to the gasket sealing surfaces
- Damage to the exhaust manifold studs
- Broken or damaged heat shields
- Cracks in the exhaust manifold
- Restrictions within the exhaust passages

Fig 2: Measuring Exhaust Manifold To Cylinder Head Surface For Warpage

Courtesy of GENERAL MOTORS CORP.

Measure the alignment or surface flatness of the exhaust manifold flanges, using a straight edge and a feeler gage. Exhaust manifold surface flatness must not exceed 0.254 mm (0.01 in).
If the surface flatness is not within specifications, the exhaust manifold is warped and must be replaced.