Cruze

Exhaust Manifold Cleaning and Inspection

Note: Do not reuse the exhaust manifold-to-cylinder head gaskets. Upon installation of the exhaust manifold, install a NEW gasket. An improperly installed gasket or leaking exhaust system may effect On-Board Diagnostics (OBD) II system performance. Remove the oxygen sensor prior to cleaning the manifold. Do not submerge the oxygen sensor in cleaning solvent.

1. Clean the sealing surfaces (1, 3) of dirt and old gasket material.
2. Clean the exhaust manifold (2) in solvent.

Warning: Refer to Safety Glasses and Compressed Air Warning in the Preface section.

3. Dry the exhaust manifold with compressed air.



4. Inspect the heat shield for damage.
5. Using a straight edge and a feeler gauge, measure the exhaust manifold mounting face for warpage. An exhaust manifold face with warpage in excess of 0.25 mm (0.01 in) may cause an exhaust leak and may effect OBD II system performance. Exhaust manifolds not within specifications must be replaced.