I have searched and haven't found anything in regards to this issue. The car hasnt ran in 4 years and I'm just now putting it back together. After the fuel pump rewire there isn't any power getting to the pump. I'm fairly certain the relay wiring is correct. There is a blue box under the dash that buzzes often. I switched out the MFI relay and had 2v at the pump. Then the 2v went away. I put the wiring back to stock and have nothing still. I used the jumper terminal and the pump still didn't run. The pump is a new aeromotive pump.

You're going to have to trace some wiring. The jumper terminal just activates the relay. I would start at the relay. Unless you put a brand new one in test the relay too. Cars sitting for years I've seen fuel pumps short out and if you try and power the jumper you get an immediate short. you may have to check all the wiring at the pump and fuel pump assembly and make sure none of those are shorted. Obviously you have a new pump so that isn't it.

@pauleyman can he jump the 12v power supply from the battery to the switch source to make the relay turn on? Obviously that’s just a temporary fix if that works

TK's9d2TSi said:

@pauleyman can he jump the 12v power supply from the battery to the switch source to make the relay turn on? Obviously that’s just a temporary fix if that works

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I tried that and only got some buzzing from under the dash. Also grounded the ground wire at the pump. Still got lots of buzzing from under the dash. Only thing I could think of is that it's somehow feeding back through the sending unit wires.

That’s strange since once you remove the trigger (12v on harness), it’s no longer part of that circuit. Let’s make sure you wired it correctly
30 is 12v from battery
85 is to ground
86 is trigger
87 to pump positive

Yes sir, it's wired correctly. I checked and checked until my vision blurred. There is a blue box above the fuse panel that buzzes and I can't figure out what it is. Does anyone know?

Also a new thread having issues with aeromotive pump.. https://www.dsmtuners.com/threads/p...-pump-does-not-turn-on.529042/#post-153764831

Relay pin 85-ground, pin 86-factory fuel pump wire, pin 30- 12v battery power, pin 87-out to fuel pump. If that's how you have it wired then if you can check relay pin 86 for voltage but I believe the car has to be cranking. Someone correct me if I'm wrong please. I'm stuck at work but wanted to try and help

I have checked while cranking and there was no voltage. Installed an extra fuel pump relay I had and voltage went to 2v and fuel pressure rose to 18psi. So the pump did turn on for a few seconds. Now there is no voltage again.

Sorry work was busy today..have you tried going back to stock wiring just to test if it works. What happens if you jump pin 30 (the 12v from battery) to pin 86 with the factory wire unplugged ofcourse to be safe. That should activate fuel pump

*sorry its late just reread previous...I would wire back to stock and confirm everything works

JPenny said:

Sorry work was busy today..have you tried going back to stock wiring just to test if it works. What happens if you jump pin 30 (the 12v from battery) to pin 86 with the factory wire unplugged ofcourse to be safe. That should activate fuel pump


*sorry its late just reread previous...I would wire back to stock and confirm everything works

Click to expand...

I have tried to use the factory wiring as well as sending power and ground directly to the plug for the pump. Using the B/W wire and the solid black for ground. The pump didn't start and the dash started buzzing. Not sure what made the dash go crazy. The pump is new but I will pull it out and test it. I have an extra walbro 255. I would have done this Thursday but was somewhat flustered and thinking there was a wiring problem. I'm working this weekend but should have an update by Tuesday. Thank you for your help. If you have any other ideas, please post them. Thanks again.

You said hasnt run in 4 years? So wasnt running right before this rewire? I would suspect all sorts..animals chew harness? Bad connectors at the pump? I'm not sure locations right off my head but I would try and check continuity from ecu/fuse box to the pump.

It has been parked in the garage and was running before. Just swapping parts from a built front wheel drive I had into this car. Ended up having some medical issues and I'm just now getting back to it.

Thanks for all the help but this was all my fault. I didn't have much time and was trying to get her running before I had to go back to work for a few day. The battery was relocated to sit on the passenger side subframe. I missed the connection for the alternator wiring and it was grounding out on the frame as well as a chassis ground. She runs. Thanks again

Glad you figured it out

Rule of thumb. Whatever you just messed with, go look there first. Glad you found it.