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 Chevrolet S10
Average mileage: 135,000 (135,000–135,000)
Exhaust & Emissions affected: 4.3L V6
2 people reported this problem
1994 Chevrolet S10 135,000 mi, Visitor
Code 32. Rough idle and stalls. Runs fine then horribly for a few moments then runs fine then horrible again. Etc..