my car has developed this wierd problem. the other day I started up the car and when I was driving down the road it acted like it was missing. kinda like a plug wire was unhooked. I checked the coil and coil wire and found nothing. the opti was replaced last april. I had a scanner put on it and it found egr, air circut, and my o2 which I already knew about.

now for the weird part. on mornings when I leave for work it will run fine for about 5 miles or so then it just goes to missing, stumbling etc. it will do it at idle, going down the road, wide open throttle etc. any help here>?

Drew

 

have you checked all the small stuff? plug wires well connected, no dusty residue on the coil/coil wire, dirty MAF sensors (unplug it and see if you're still missing)? could be your o2s since it seems you're not missing in open loop. I'm no expert by any means...i've just finished chasing down a high rpm miss which turned out to be a corroted coil wire. When were the spark plugs last changed?

Good luck.
wade

 

heres another post that sounds like a burnt plug wire,first check ALL your plug wires especially the #7 one in the back,take it completely off if you have to,as you cant see it all as its right behind the exhaust manifold.(mine was burnt almost all the way through)could also be a loose or fould plug(s)

 

I ahve tried a coil and coil wire from a friends car. It misses under wot as well. The computer is always in open loop " long story" checked the mass air too...

Drew

 

have you checked for arching in the wires?
so you have a high RPM miss? or accross the band? and only at WOT?

wade

 

http://web.camaross.com/forums/showt...hreadid=143509

 

it does it at all rpm ranges and at idle and at wot. but first thing in the morning it runs ok for the first 5 miles then it goes to stumbling

 

ttt

 

it is not shutting down to lean from the rich mixture when the engine is cold, when first starting out...MAF, O2 sensors???

 

Mine was doing the same thing a couple months ago and it turned out to be the o2 sensors. I didn't think at first that they could cause a miss that bad, but they did. The miss is much worse than a burnt plug wire which usually occurs in low rpms and high rpms, not throughout the whole range. Oh and also, DO NOT under any circumstance replace with Bosch o2 sensors, thats what I originally bought because Advance Auto couldn't get any AC Delco's. They lasted all of 2 weeks before they crapped out and it started doing the same thing. I ordered some AC Delco's online and it has been running better than ever since. Hope this helps,

Derek

 

Had the same problem, could of SWORN all plugs and wires were fine....4 times I checked what I thought was everything...


cracked plug. Felt like a jackass. lol