Illumination of the Check Engine Light can be caused by a loose or worn gas cap.Google+
Car Problem Reports
Saturn SL Check Engine Light Due to Gas Cap Issue
Saturn SL Problem
Average Mileage: 119,000 mi (69,000 mi - 169,000 mi)
Visitor, 2002 Saturn SL, 69,000 mi
the light comes on &machanic turns it off 10 mins later its bk on,been doing this ever since th 2 wk after i bouight itits bk on now,.i love my car but not the aggervation of the (check engine )light kleeps comen on &the key keep messing up,takes 3-4 trys to ghet the car started &i've use 3 different keys thinking they wore out but thats crap cause i don't drive in winter,only 69000 mile
Bought replacement gas cap. Took about 2 days for light to go out--might not go off right away.