Exhaust Manifold Cleaning And Inspection
- Do not use the exhaust manifold-to-cylinder head gaskets again. Upon installation of the exhaust manifold, install a NEW gasket. An improperly installed gasket or leaking exhaust system may affect on-board diagnostics (OBD) II system performance.
- Do not reuse the exhaust manifold bolts (4). Upon installation of the exhaust manifold, install NEW exhaust manifold bolts.
- Clean the exhaust manifold (1) and heat shields (2) in solvent.
- Dry the exhaust manifold with compressed air.
- Inspect the exhaust manifold-to-cylinder head gasket surface for excessive scratches or gouging.
- Inspect for a loose, damaged, or cracked heat shield (2).
- Inspect the heat shield bolts (3) for damaged threads.
- Use a straight edge and a feeler gauge and measure the exhaust manifold cylinder head deck for warpage.
An exhaust manifold deck with warpage in excess of 0.25 mm (0.01 in) within the 2 front or 2 rear runners or 0.5 mm (0.02 in) overall, may cause an exhaust leak and may affect OBD II system performance. Exhaust manifolds not within specifications must be replaced.
WARNING:
Refer to Safety Glasses Warning .