grantpa
Full Access Members
My Expy has a slightly, almost undetectable, rough idle. It's a bit more pronounced at higher RPM's. BUT NO CODES. I'm a bit stumped as I've replaced all my COPs, due to earlier misfire codes in multiple cylinders. I've also removed the injectors and cleaned them. Also, I've taken it to my mechanic who scanned it and was stumped and could find nothing to lead him in a particular direction. He suggested that I drive it for 300 miles or so (drive cycle) because a couple of the I/M readiness parameters (Evap and Cat) were incomplete and he thinks it won't throw a code until the drive cycle is complete. The problem is the truck is NOT registered currently due to this "miss problem" and it will NOT pass the emissions test until the I/M readiness is complete. Catch 22, right? Any suggestions to point me in a direction would be immensely appreciated.
