mooseknuckle3835

iTrader: (1)

After hours of trouble shooting and doing a complete rewire on the fuel pump relay I figured out there was no signal from the ECU. I have search all night and every related post never seems to have the final answer posted on how they corrected the issue. I check for continuity and its good. I can jump the relay to 12v and the pump will prime so i know its hooked up correctly.

I assume the vats has been disabled since the car will start and run once the fuel relay is jumped. And i do not have a BCM since this a swapped car.

Thanks in advance

bjamick

iTrader: (31)

Remember that the PCM supplies 12V to the relay, not ground like everything else. So in other words the PCM wire should be going to either 86 or 85 on the relay. And the other side whichever other one you have left either 86 or 85 should go to ground.

mooseknuckle3835

iTrader: (1)

I would like to point out again that I have tested the Green/White wire for the fuel pump and it has NO 12volt out. Not for 2 seconds prime and not after the car is running.

This is a 98 ls1, ecu, and custom modified harness from Hinson.

bjamick

iTrader: (31)

Do you have all the pink wires for the PCM hooked up to keyed on 12v? It has to have power before it can send out any.

If you have continuity between PCM and fuel pump relay control wire then you know it's another issue. Could be a ground possibly, or not enough of them.

mantycarguy

Depending on what year pcm you are using the GN/white wire could be a pcm ground or a 12 volt constant in hot /run mode. To figure out which one you have take a test light to bat+ and probe the gn/white wire while turning the key. Make sure it is not connected to the relay while testing. If your test light lights for approx. 2 seconds and the goes off you have now determined that the pcm controls the ground side of the fuel pump

tjohnson

Iam having the same issue. With my 98 ls1 swap in 68 camaro. Car will start and run. But no signal Want to hook up the correct way by using the computer. What did you find out

tjohnson

Hey just wanted to say i found my problem with the no signal to fuel pump relay. BIG dummy must have blown a fuse sometime between my last start up and wiring my fuel pump. Check my power to computer found none. Can anyone say duhhh! Well at least it wasn't anything big. Funny I have my ASE in electrical/electronic systems. Just shows you can over think the issue sometimes.

blown383z28

iTrader: (3)

kind of a old post but, anyone find more out on this kind of problem???

blown383z28

iTrader: (3)

no one??

bczee

iTrader: (12)

If you read post #7.. it was a blown fuse to the PCM.. replaced and problem resolved !

blown383z28

iTrader: (3)

if you read the threads it says nothing about mooseknuckle3835 finding his problem.

Bilster

iTrader: (21)

His last activity was November of last year. Your best bet is to post your actual problem and see what you come up with. There is plenty of members willing to share their knowledge.