I have been going through and replacing some of the needed tune-up items on my 94 SE, with 135K miles, and I have now run into a miss at idle speed only. I have replaced the following:
plugs, plug wires, Oxygen sensor, air filter, pcv valve, installed a 180 thermo, and no coolant leaks present. I would appreciate any help to eradicate this miss.

Thanks...........

I could be wrong in saying this but it might possibly have something to do with the input that the computer is getting. It could be a bad sensor. Possibly a dirty air temp sensory or maybe a bad MAF sensor. But I think those would have put out a trouble code. It could be worth it to test it out though.

I just replaced the TPS on JSeabert'* car for this problem, and a few more. Depends on HOW the TPS fails what it will affect. It could have an unstable reading at the low end, and be fine elsewhere. Had one fail that way on a 94 suburban once. Just a thought. Does it really sound like a miss, or could it be just a rough idle?

It is in fact a rough idle, today, it died while at a stop light. Car runs fine when driving, gas mileage is better than before, just problem at idle. Will a local auto parts store be able to run a check of the computer.
Thx

Yes, they will. You might be running a bit lean....clogged injectors.....poor fuel pressure....could be alot of things. Codes tell all....usually.

thanks will............

Add to the list of possible things: The idle air control valve. That valve lets a little bit of air around your throttle plate when at idle, so that your engine doesn't stall. It may also be dirty or clogged in the idle air passageway.

But Will'* right, it could be a host of other things.

If I were you, I'd take the throttle body off and clean it. It'* pretty easy to do, just get some carb cleaner and a toothbrush, and gasket sealant for when you put it back on. You can pull the IAC out and clean it and the passageway. Just make sure you don't remove the TPS, unless you have a digital multimeter and don't mind recalibrating it.

Did anyone mention the EGR Valve? I had this happen to my Blazer. Ran fine at driving speeds, Idled like it had a cam--sometimes died while idling.

Scan for codes--don't guess. It costs too much to guess.

One way to make it easy for codes now and for later uses do what I did. Run to your local wal-mart or fleet-farm or large warehouse store and go to the automotive section. For $20 you can pick up a code reader and code book. It has come in handy quit a bit for me. The code reader plugs into a plug by the gas and brake pedal basically right below your steering column. All you do is plug it in turn the ignition on and count how many times your "service engine soon" light flashes it always flashes 12 first which is the diagnostics mode code which doesnt mean any thing and after that flashes 3 times it will tart flashing service codes to you. Its really easy and the code reader is fairly cheap. Hope that helps you. Oh the code reader is in a clear box with a clear incert and its just called a GM CODE READER. The only thing is it only goes up to 1995 gm vehicles because after 1995 they swiched from a 12 pin connector to a 16 pin connector. Good luck.