Illumination of the Check Engine Light may be the result of a loose or worn gas cap.Google+
Car Problem Reports
Chevrolet S10 Check Engine Light Due to Gas Cap Issue
Chevrolet S10 Problem
Average Mileage: 89,776 mi (47,000 mi - 183,000 mi)
Visitor, 2002 Chevrolet S10, 78,000 mi
"service engine soon" code-303 (missfire on no three cylinder)- light keeps comeing on and after I drive it for a few days it goes off then the same again in a few days. I've changed vaccum line;s under the hood. putnew spark plugs & wireing, new coil, & new GM gas cap,- the only thing I haven't checked is the vaccum lines to canister and canister
Engine light on, test meter code shows evac. Changed gas cap and didn't go off. What next.
Visitor, 2002 Chevrolet S10, 67,000 mi
Local AutoZone found the problem/ new gas cap resolved the check engine light!
Tightened the cap?
Visitor, 2003 Chevrolet S10, 80,000 mi
check engine light came on, got the code ran..came to be emissions code...put a new cap on a never seen the light again
Visitor, 2003 Chevrolet S10, 62,000 mi
REPLACED GAS CAP
Check engine light came on just before the inspection was due. Had the code read. The guy at the parts place recommended replacing the gas cap first. It did the trick.