I have a 94 z28 and have had the weirdest problem with it randomly not starting and shutting off on me. the problem started about 4 months ago, i messed around with the fuel pump relay pig tail and it would start up and it did this about once a week for the next 2 months. but now it has problems starting every day after driving for a while, it wont start till i haven't driven it for about 3 hours and runs kind of rough, i've replaced the coil and ignition module as well as the fuel pump relay and the pig tail for it. I'm completely stumped by this issue, i do have a check engine light that only comes on idling under 35 and my lights get dim and the tack on the speedometer shoots up and back down when i cut the car off but that has happened since i bought the car. Any help will be greatly appreciated!!

 

Scan it for codes.

Since you are a newbie I'll assume you didn't read the notice - stickied topic "DO NOT POST HERE......UNLESS". Advanced Tech is not for problems like this. I'll move your post to "LT1 Based Engine Tech".