92 Camaro, 3.1, I just bought. 127k on it. Have replaced cat, EGR, MAP.... Sometimes it runs smooth and great then usually at a stop itll cough and run very sluggish, like no power, hard shifts, tach bounces all over and it can stall, for the most part it doesnt. Any ideas anyone???

 

Check your timing and Idle screw.

 

I also posted in general troubled shooting. If you could please read what was posted in there too. Same subject.
Thanks

 

Okay the same thing happened to my V6 3.4L 1994 Camaro. Check you plug wires I bet on of the wires has a hole or a crack in the wire and you are runing off 5 cylinders

 

That or your TPS sensor is bad, is the check engine light on?

 

Check your ground from the battery to the body right by the headlight. I had an 86 that ran fine then it started running like your. Checked the little griund wire coming from the negative terminal and sure enough the ring terminal had broke. Put a new ring terminal on and screwed it back to the body and the car purred like a kitten again.

 

When I bought mine, Mine did the same thing, Until I started my car in the dark and checked under the hood. I had 2 arching Plug Wires, so I replaced all of them and replaced the spark plugs only to find that they were fried.

Once all that was done, it rode like a champ.