Hello! i have a 94 camaro z28 its been sitting for about a year due to a no start issue i had. It would run for a few minutes than die.now it wont start at all. I replaced the fuel pump on it and the optispark and fuel pump relay. I had the coil and ICM tested good. I havent checked for spark yet after the opti install but when i have the key on engine off my fuel pump keeps priming off and on. I can hear the relay clicking on and off on and off really fast. i swapped the relays but it still does it. what could be causing this? I have a code 41 it says Electronic spark timing is open. Any help is appreciated thanks!

 

There's an open circuit to the IC Module. Check for 12V from the coil connector. Check for a good ground from the ICM to the block. Shoebox has the wiring diagram that will tell you which wire colors go to which terminal. If you have 12V and a proven ground, the ICM could be faulty. You can have it tested at an auto parts store.

Never heard of the fuel pump relay behaving the way your is. Would appear it is getting an intermittent ground from the PCM.

 

Well took my icm in to parts O riely and it failed. When autozone tested it they said it passed hmm. Oh well ordered a new part see if it fixes the problem. And the clicking relay and fuel pump was because my obd scanner was plugged in the obd port while the scanner was off.

 

So i installed the new ICM and cranked it and it started for like half a sec and then it turned off. I keep trying to start it again and it acts like a dead battery. The volt gauge will drop all the way down if i press the gas pedal. If i dont press the gas pedal it will crank hard and slow at the same time back firing at the intake and studdering until the volts drop down. I tried jumpstarting and i get the same issue. Took the battery in to get it tested and they said it was good and fully charged reading 12.8 volts. Not sure where to look at next. my battery cables are clean and tied down tight. Any help is apreciated. thanks