My camaro has been running like *** lately.... backfires all the time, no throttle response, tach bounces around everywhere. I thought it was perhaps the valves, so i relashed them and still had the same problem. One thing i did notice is that the problem only happens after the car has been warmed up....i took it out the other day and beat the hell out of it when it was cold and it ran like normal - - drove around for a while longer until it warmed up and it started back firing and dying. I was thinking that maybe it could be something related to the ECM once everything warms up....any suggestions are greatly appreciated as I am tryin to sell it.

BTW, engine temps are normal, no engine light or codes...the thing will just randomly backfire and die

 

I would suspect the ignition module, the pickup coil, the ignition coil or bad wires before blaming the ECM. You say the tach bounces around so suspect primary ignition stuff...