The EGR valve may stick open causing a rough idle and the Check Engine Light light to illuminate. Our technicians tell us that a piece of carbon may become stuck in the valve causing this problem. Cleaning the valve will usually correct this condition, in some rare cases the valve will need to be replaced.
Check Engine Light/Rough Idle Due to Stuck Open EGR Valve on GMC Sonoma
Average mileage: 195,000 (195,000–195,000)
Exhaust & Emissions affected: 4.3L V6
3 people reported this problem
0 people shared problem details
...d flushed radiator. Ran fine for a day then this. Checked vacuum lines and they are fine check engine light on as well.
A Loose or worn gas cap may cause Check Engine Light to illuminate.
engin light is on. engine runs rough at idle, auto zone can not read the computer, why cant the...