I have a 95 z28 with a 150k miles on it. The past few months ive been having a horrible miss/stumble at part throtle and heavy acceleration under 1k rpms to 2k rpms. It ran better when it was cold and got worse as it warmed up. Now it wont even start up, its turns over but doesnt start. Ive put in many new parts such as:
EGR valve
o2 sensors
Fuel Injectors
Ignition coil
fuel filter
Platnium Plugs and wires

Does any one have any idea on what it could be?? i have a new distributor coming so hopefully ive found the problem??

 

You need to verify that you have spark at each cylinder, verify that you have fuel and that the injectors are firing.

Can you hear the fuel pump prime when you turn the key on?

Have you tested the fuel pressure?

 

I checked the fuel pressure , a ok on that one...i also checked to see if i the fuel pump goes on when i turn the key on, of course it turns on....the only possible problem with my symptoms could be the opti....just wanted someone to varify it....thanx

 

Since I just found out today, check the ICM. That was the problem with mine. I changed the coil, plugs, plug wires, opti. I have a 140k on mine so I don't feel bad about replacing the other, but it ended up being the ICM.