Need help bad Ihave a 87 Z28 I dropped a 350 in place of the 305 TPI 3yrs ago. Recently did major overhaul with new comp. cam 30lb injectors head work adjustible fuel pressure regulator @45psi large runners and headers.Also new motorvation custom chip.This car will not idle installed 2400 holeshot converter,plugs,wires,cap,rotor,coil,pick up,module,and all new sensors.Checked wiring and found that I had little to no spark @ plugs will not even light timing light which is good I checked it on to other cars.I hooked spark control back up and timing light works but of course cant set timing like that unhooked that little tan and black wire engine wont idle timing light dosent work but engine starts and revs without hardly a miss till you try to let it idle and it dies.All gauges register in norms everything else works great.Does anyone have any idea why I would have better spark with ESC hooked up than without or why I have little to no spark at plugs period.Any educated guess or reply would be greatly appreciated.I am clossse to brrroke.

 

Get your battery checked.

 

Tried a battery out of one of my other camaros changed nothing.Batteries out of my 90 RS trashed EFI in it for Carb. It was a TBI. 87 z28 TPI sort of fond of the throttle responce from it.I also checked all grounds and for loose wiring no dice. Thanks for the advice still hopeful for cheap fix.