i have a 93 z28 and it runs fine until u floor it and then it starts missing, its a auto, and i was wandering if itmight b the fuel injectors needing replace but i tried injector cleaner and it didnt help, its not the plugs and wires cause i just changed them, to me it acts like my motorcycle when the plugs are fowled out and then the gas burns off and has more power, i was wandering if any one could help me?

 

I would look at the infamous Opti first. Do a search you can miss it.

 

How long has this been going on for?

Usually when something like this occurs you're either dealing with a spark or a fuel issue. From my experience it's usually spark.

However, fuel is easier to rule out so I check it first. If you have a fuel pressure gauge, hook it up and see what kind of pressure you have. Should be around 43 at idle. You'll also want to check it at wide open throttle and make sure it's not dropping off significantly.

If you rule that out you can move on to ignition. It's simple to remove the ignition control module and take it to Autozone to be tested. It's the small electronic piece that's mounted to the same bracket that the coil is mounted to. If the fueling is ok, the plugs and wires are ok, and the ignition control module is ok then that really leaves only one last culprit- the opti.