well, recently ive been getten a check engine light, that will come on after the car backfires after driving it for awhile. Then it will die if i drive it for more than 20 mins after that. Today it happened and I noticed after it happened the engine temp dropped signifigantly and the check engine light came on. Any ideas? Thermostat? Will the lt knock module help me? Dealer said it was a burnt wire, i replaced it... still its no good. Thanks for the help.

 

The engine temp drops because the fans kick on. I know its easy to point fingers at the opti but in this case Id put my money on the opti. Next time the SES light kicks on just drive over to autozone and have them scan the car for ya to see what code is stored in the PCM... that is if they still do that courtesy.

 

I guess they can only scan obdi2

 

You are correct, Autozone can only do OBDII. Even though the light is out the code will still be there. Have a reputable garage scan it.

 

Thanks for the help guys.

 

I ended up buying a cable and I determined it was the opti. Thanks