Car started stumbling really bad yesterday. Acting like it wasnt getting enough fuel or air. Before this happened, the service engine soon light came on for about 5 minutes and went back off. I shut the car off and got back in about 5 minutes later and that's when the stumbling started. At WOT there is no stumble. Today, tried to get it scanned but the SES light wont stay on long enough. Only stays on for about 5-10 seconds and then goes off and wont come back on for a long time. Turned on the ignition and unhooked the battery. Left it for about 5 minutes. Stumble has been gone since the battery was unplugged but the SES light still does its thing of coming on and then going off after a few seconds. I doubt it would be on long enough to even scan for a code. Car has 82K on it. Nothing in terms of sensors has ever been changed. Any thoughts?

Thanks

 

could be an opti on its way out. did you touch anything under the hood lately? could be a loose wire (plug/coil) as well. check under the water pump to see if it has started to leak.

 

Havent been under the hood to change anything. Popped it last night and checked to make sure everything was still connected good.

Would an opti going bad throw a code?

 

Any other insight on this one?

 

yes it would. did you check your water pump?

 

Everything under the hood seems to be good. Everything is connected really good. Nothing leaking from the water pump. However, I did disconnect the battery and let it sit for about 5 minutes. Hooked it back up and since then the car has not stumbled at all. About an hour after that the light came on 3 times for about 10 seconds and then went right back off. Havent had any more trouble for 2 days.

 

thats the oddest thing. i have no clue what to say. is ther any way you can log your car with datamaster?

 

Well, my luck has run out. Car started acting up again today. And I mean bad. Its running pretty rich and I dont even know where to begin to start. All suggestions are welcomed. As suggested above, would the optispark going out cause it to run rich? Also, the SES light has still not come back on so I dont know what the deal is.
Thanks for the input

Joey

 

Try to get her scanned and see what codes show up. O2's will manage to make your car run rich. Also, the MAP sensor can too. I would place my money on the O2's gone belly up. Just my .02

 

my car is stumbling bad at idle as well, idling really low(200-400) and running rich. All this after an opti swap. Are you getting the same kind of stumbling problems too, because my SES light goes on and off as well.

 

I replaced my O2's cause it was running rich. I ordered some Catco ones from summit. DONT ORDER AFTERMARKET O2'S....Get GM ones. I put them in, and my scanmaster was showing it was stuck at 445 volts. The SES light comes on after driving the car for about 5 min(after it warms up)..and it runs reallly rough.

Replace the O2's, order some from Jason cromer...again, get GM OEM O2's(<---hehe thats funny)

If its not O2's, well thats less than 100 bucks down the drain..and you could prolly use new ones at 80k+ miles anyways.