I've cleaned my fuel system, new fuel pump, replaced my spark plug wires and I have a new ACCEL coil and cap and have checked the timing. Spark plugs were new 6 months ago. Car starts and runs good until it warms up, then it seems to have some sort of a miss. When you accelerate it seems sluggish and you can feel the vibration and you have to put the gas to the floor for the car to kick down. The previous owner let it sit for long periods at a time and I think that I may have a bad injector. Car also is hard to start after you stop it and let it sit and then restart it.

 

Welcome Aboard!!



Sounds like an oxygen sensor issue. Your car ignores it until it is at temp or a predetermined amount of time has passed, which ever doesn't come first. If you don't know the last time it's been replaced or if you do and it's been a while it's worth changing even if it isn't the problem. This sensor is very important and easily ruined/warn out.


Sounds like leaky injectors. These let fuel leak into the combustion chambers as your car sits which floods it when you go to start it. After the car sits for a while this fuel has time to evaporate and the car should start fine. I don't know what you did to 'clean the fuel system', but if it was one of those gas tank additives it probobly didn't do the trick. I used that stuff all the time and then sent my injectors to get a sonic cleaning and flow match and the guy said they were in horrible shape (and a few were leaking). Here is where I had them done at:

http://www.cruzinperformance.com/

NOTE: 'Sounds Like' doesn't mean these are no doubt your problems. These are just some avenues for you to explore.

 

I appreciate your help. I replaced the oxygen sensor last year when I installed my SLP headers. So I am not quite sure that it could be the oxygen sensor unless I installed a faulty one. This weekend I am going to pull all my new plugs and check for any problems and also re-check my timing.

I had the front end of my car professionally cleaned at a Pontiac dealership. They sprayed it directly in the throttle body and turned off the fuel pump and ran the car with the cleaner through the fuel rail.

I do feel that it could be an injector problem that is causing all of my problems and I will be replacing them all as soon as I get the funds to do so.

 

Here's a picture of my 89 T.A.

 

The picture size must be too big, I'll try to decrease it and re-post

 

Is it a heated unit? Some people have had issues with headers and non-heated oxygen sensors because they aren't gettign to operating temp on their own.

Better then what I expected although, as you said, I'd still consider them suspect.