1996 LT1 5.7L out of Pontiac Firebird that has been put in a hot rod truck by another individual with the original wiring harness cut and spliced to fit into the truck. The truck will crank and crank until the battery goes dead an wont ever fire and run until you give it a breath of ether the it starts and runs great. Shut the truck off and restart it no problem with no aid. Wait a couple hours and it wont start again unless you give it aid. I have gone thru everything I know and tested fuel pressure, spark, air. Its has a new opti spark, plug, wires and like I said it starts with aid and then will restart everything you shut it off unless you let it sit for an extended period of time. I have verified power to the ecm of constant power and key power and have my 5V ref. but Modis wont communicate with just the key on. It will communicate while the truck is running though. Its like it loses its memory until you force it to start and then it comes back to life. I am pulling my hair out has anyone ever run into a similar situation or have any advice? PLEASE HELP ME!!!

Thanks Terry

 

This is 82-92 Camaro/Firebird forum EXCLUSIVELY. Not a general tech Q&A or whatever. LT1 isn't a feature of our cars and as such doesn't belong here. Only time it's discussed here is if somebody is putting one into a 82-92 Camaro or Firebird.

You'll have better luck on a 4th gen forum or other such, that's NOT devoted EXCLUSIVELY to some other type of car besides one that came with that motor.

 

got it, thanks for the reply

 

Could be a vats issue disabling fuel pulse. Lt1 is stretching the memory back a ways, but if you have access to a scanner you can check vtd fuel enable