Visually inspect all electrical wiring, looking for chafed, stretched, cut or pinched wiring. Ensure electrical connectors fit tightly and are not corroded. Ensure vacuum hoses are properly routed and are not pinched or cut. Inspect air induction system for possible vacuum leaks
This article supersedes TSB 02-9-1 to update the service and part information.
Some vehicles equipped with the 2.0L SPI engine may exhibit a malfunction indicator lamp (MIL) illuminated and diagnostic trouble codes (DTCs) P0300 through P0304 stored in memory. The vehicle may also have a rough idle or reduced power condition, and/or may stall at an idle. This may be caused by sticking exhaust valves due to excessive carbon build-up.
Check for faulty fuel injectors and ignition wires. One or more exhaust valves may be temporarily sticking due to carbon build-up between the valve stem and guide. If the diagnostic checks point to a sticking exhaust valve, the cylinder head assembly may need to be replaced with a new level cylinder head assembly with revised valve guides, revised exhaust valves will also need to be installed to help prevent carbon build-up