4 Wheel Drive/SUVs: service engine soon light, gmc dealer, gmc jimmy

Question
my 93 gmc jimmy 4x4's service engine soon light  comes on for a while and it may go out for a while but comes back on. i have changed the plugs and plug wires and some times it still seems to idle kind of ruff. what do i need to do to make the light stay off? thanks jeff

Answer
Jeff, this is a reminder light not a trouble light and is normally activated by mileage driven.  There is usually a small hole near the speedometer that is used to turn the light off.  If you cannot find it call your local GMC dealer and ask the service adviser how to turn it off.  Best of luck.  Bud