I have a 1994 Camaro Z28 (LT1) and its been running like garbage. I brought it to the mechanic for new plugs, wires, O2 sensor and fuel filter. The car is still running bad and the mechanic told me that the battery is showing 14.4 volts but only 12 volts at the computer (bad ground somewhere?) and this may be why its running badly. Anybody ever heard of this before, if so does anyone have any pointers as to a solution? Thanks in advance.

 

Probably the ignition switch or it's connector. It seems pretty common to lose some voltage there.

 

Check the voltage at the fuel pump, and at the injectors. The PCM will work fine with 12.0V.

 

I think you will probably find that everything that is ignition switched has the same lower voltage. That is why I suggest the voltage drop is where I said above.

 

I would be surprised if the pcm was the problem. Does it feel like it's missing? My guess already is that it's the optispark. I'm replacing another one tomorrow. Old one was full of rust. I have never had a fuel delivery problem, only spark problems. Spark will be burned wires, old plugs, bad opti, bad ignition module; but I've never had an ignition module go bad.
You could run some fuel injector cleaner through it which I've heard sometimes will cure a driveability problem after everything else has been tried, but that's probably not it. If you don't know what a miss feels like, pull a plug wire off and drive it. If it feels like that when you drive it normally, it's the opti.