Not overheating. The studder happened on take off(M6) and shortly after on interstate, the light came on. When the car comes up in temp it studders. Tested out and redline to see if studder was in higher rpm, but not. Just the one cough.

NE thoughts or ideas. Maybe plugged cat.

Finch

 

May or may not be related symptoms. With the engine cool, remove the radiator cap and see if the coolant level is truely low. If the level is to the top, your coolant sensor is not working properly. The coolant sensor (located just below the radiator cap) is famous for failing on these cars. Sometimes cleaning the inside of the sensor cures the issue, otherwise replace. If the level is low, refill the radiator, refill the overflow tank and monitor your coolant over the next couple of days. Any white "smoke" coming out the tailpipe when running?

 

No white smoke, but if this helps with the issue, I think that I am runnin rich. I have small backfires on decel. I thought it was backpressure. Maybe it is maybe it isn't I also threw an egr code, but I threw that when my IAC crapped out.

thanx

 

My guess is your water pump is leaking on your opti and causing your misfire and coolant level to be dropping

 

I will definateltly check it out if that is the case. The thing is, that it only misfired once when it was heating up. My car runs cooler than most I think and in city driving, it will heat up around 40* more, in which case I feel noticeable power loss and the one misfire.

thanx for the replies.

 

This coolant lights come on and off like no other. Mine came on and off like 5 times at the track and everything was normal........fluids perfect, temp at like 170.


Anyone know the part number for the coolant sensor?

 

Actually I just replaced my coolant sensor less than a month ago, so I happen to have the part number handy: 10096163
Cost me $41.41 with my GM discount. But thats in Canadian dollars.
Hope that helps.