Well when I get around 2200 rpm's the car bogs real bad and starts to shake. If I go WOT, once it gets past around 3000 rpm it screams like nothing is wrong, but between 2200 and around 3000 it runs real bad. This just started yesterday. Last week the car was running fine, until I would go WOT it would hesitate a little right before it would shift.

It runs good right when I start it up, The problems occur about 2 miles after I am driving down the road....

All the plugs look good, so I don't think that's it. I have a feeling I know what it is


Anyone have any ideas?

 

try unpluging the o2 sensors.

 

Does a bad opti throw a code? I just went up to discount and got them t scan my car.... only code I got was code 23 manifold air temp low. I thought if I had a burnt plug wire, then it would tell me which cylinder wasnt firing.



actually, thats a good idea. I will try that.

 

code 23 is about the IAT sensor on the air inlet elbow, saying the voltage is high causing lower temperature reading than is actually going in. I"d replace the IAT, its not that expensive.

 

would that cause the car to run bad?

 

The short answer would be yes. Its telling the pcm the temp of the air going in is quite a bit lower than what it actually is and pcm isn't regulating the fuel properly to compensate. So yes, it can and will make the car run funny. First and foremost though, since its reading high resistance, I'd check to see if the IAT is even plugged in? If it is, then I'd just replace it.

 

Just replaced the IAT, still running bad. Now it stumbles really bad right before it shifts if I go WOT.

 

Ok, I'd check fuel pressure now. How recent did the car throw the code?? That may have been a stored code from the past that never was deleted and could have no relevance to your current situation. Check fuel pressure and try as suggested already removing the O2 sensors to see if there's a change.

 

Well I replaced the optispark thinking that was the problem. whole days work and $240, and it still runs bad. Atleast I have the ease of mind that my opti will last a long time now.

I am going to try the 02 thing tommorow. My friend also said his car ran similar to mine right before his coil went bad, so I will try that out.

 

Check the wiring going into the IAT harness as well, you could have a bad connector or wiring or both.