I bought a none running 90 vette 3 years ago and have (couple of months ago)finished a complete rebuild on it from the ground up.The problem is it still doesn't run.Everything works perfect as it should except the fuel pump won't come on.I have changed the ecm(new rebuilt from chevy)I have changed the rear wireing harness,I have installed all new fuses and silonoids(?)The only thing that is original is the bcm.Could that be the problem?The car has 225,000 miles before rebuild.I tried to buy a new one to set the miles back to zero but couldn't find one so I left the old one in.I could sure use some help.If anyone has any ideas let me know.I sure would like to go for a ride Thanks/poppy53

 

The car also has all newer wiring harnesses off of a running low mileage 90 vette that was involved in an accident and totaled by the Ins.Co..All relays have been replaced with new.The engine will fire with a shot of starting fluid.I put 5 gallons of gas and the gas gauge does work.The fuel pump assembly is new also and I have jumped the pump to make sure it works.
Thanks/Poppy53

 

Have you checked to see if there is spark? ECM will not ground the relay unless it sees an ignition signal.

 

Yes there is spark.

 

Where does the ignition signal come from?

 

From the pickup in the base of the distributor through the ignition module. Do you know if you have injector pulse?

 

Here is a wiring diagram for fuel pump relay. Check to see if fusible link is good by checking for power at the relay. You should have power on the red wire and dk green/white during cranking. Also check fuse #1 to make sure signal is getting through to pump.

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