3.4L misses when cold - HELP

[Ryan Lieving]

I bought a 1995 camaro 3.4 V6 auto with 54,000 miles, one owner in great shape. I did some maintenance such as new wires, plugs, fuel filter, air filter, flush transmission/coolant, and brakes. The problem is when starting cold then driving to the first stop sign about 300 yards away it hesitates when stopping at the stop light. RPM will fluctuate then level off. Once it quit running and sometimes it backfires when accelerating when cold. After a minute or two the engine warms up and it runs fine. I took it to my Chevy dealer and they could not find anything wrong. It did not show any codes. Next they will attach a recorder to the data port and when it does it I push a button and it recordes what is happening. I think this problem will be hard for them to find. I am new to a Camaro and this forum and would appreciate any help. Thank you.

[nikkev]

Hmmm,not real sure on that one.Are you sure the plugs/wires are in good shape?Maybe some fuel system cleaner,maybe the injectors are dirty?Good luck.
Kevin

[v6maro]

sounds like the valve guide seals
does it puff a little smoke when you first start the car up?
-Steve

[Ryan Lieving]

V6maro
No, it does not smoke on start up. I have since found a Chevrolet Tech Service Bulletin for the 3.4L V6 dated Feb. 96 that describes exactly what the car is doing. It says a problem caused by the PROM. My dealer is going to find the TSB today and let me know. Probably needs a revised PROM. Well see. Thanks for your reply.