Engine replaced with new at 85,000. Current odometer, 122,672. Since engine replaced, "check engine" light comes on after several hours of high speed Interstate driving. Once lit, stays on for hours, even overight. All gages read properly. Have called "on-star" for diagnostics. They found no problems or engine misfire. Light went out before taking car to GM service. GM ran diagnostcs test and found no problem. Have not been able to make light come "on" with local driving but it reoccurs after one or two days of long distance travel.
Do you have any suggestions for "most probable" cause.
Can you recommend an inexpensive code reader so I can read the trouble codes related to the "check engine" light and reset the trouble light.
have the same problem?
Wednesday, January 9th, 2008 AT 4:32 PM