Ok I just got my PCM back from being tuned and I'm still having a problems at WOT , when the car gets to around 4-5k rpms it just wants to pop and backfire and wont accelerate or shift. Like in the video I'm having to let out of the gas for it to change gears. Runs fine with no hesitation otherwise until WOT between 4-5k rpms. I've narrowed it down to either the Ignition Coil,Plugs and Wires,O2 Sensors or the opti. Can someone point me in the right direction?


http://s716.photobucket.com/albums/ww161/heatherdanielle87/?action=view&current=MVI_0144.flv

 

Did you drive around normally for 20+ minutes to allow the PCM to calibrate??

 

Check your plugs for fouling, burned electrodes or excessive gap.

In the dark, pop the hood and look for arcing on the coil and plug wires. Check carefully for wires burned on the exhaust.

Scan the PCM for Opti codes (only sets codes for problems with the optical sensor).

Have you ruled out valve float? What mods do you have? Might want to include that kind of info in your "signature".

 

Please post a topic only once, on the correct forum. You have this on "General.....Tech". I'll close that one. I already posted an answer there. By posting on multiple forums, you end up with people wasting their time posting the same thing someone else may have posted already on the other forum.

 

Just got back from a ride and it seems like about 30 minutes or so after when the car warms up the SES light comes on and ALOT of the hesitation go's away, It stops backfiring and popping at high rpms although there is still a little hesitation. Can anyone explain how the SES Light is causing it to smooth out?

 

No.... but it you scan it for codes, it will tell you what part is malfunctioning. If the default response of the PCM is to ignore the part that caused the problem, you will know what is screwing it up.

 

Sounds like Opti/Coil issues.

I'll move it to the LT1 Forum.

 

I had autozone try to scan it for codes and the guy tried 3 different times and the scanner he was using kept sayin Cannot establish a connection or cannot connect the pcm or something.

 

I would replace the plug wires

 

I plan on changing out the plugs,wires, and coil tomorrow , still debating on whether to go ahead and change out the ICM too.

 

I'll bet he saw the 16-pin ALDL connector, and thought it was OBD-II. When you hook up an OBD-II scanner to an OBD-I PCM, it can not connect. You need an OBD-I scanner, with the correct 12-pin->16-pin adapter plug, or use Shoebox's jumpers:

http://shbox.com/1/xraycable.jpg

 

How many times did you post the same thing? This is the third version I've found. PLEASE post a topic only once, and only on the correct forum.

It just wastes people's time giving you duplicates answers.

If you accidentally double post a topic, as this one appears to be, you can delete the duplicate post by simply clicking on the "EDIT" button in the lower right hand corner of the post, then using the "delete" option in the pop-up. But delete it BEFORE you have multiple threads going with multiple responses.

 

Id do plugs and wires first and even if that isnt it a tune up is a good thing

I had that same problem with mine and put some new plugs and wires on and i was good to go.

 

Merging the 3 threads.... so its going to look a bit weird.

 

It was the coil wire, It got rid of about 80% of the hesitation.Changing plugs and wires next