I am not getting the two second priming to the pump i have checked the relay by putting power to the g pin on the aldl and i can hear the pump but not getting it when i turn the key on. i also have checked the fuse by the battery and it is fine. any ideas I'm stumped

 

Is there voltage at the relay coil? Connect a meter and watch it while an assistant turns on the ignition, since you'll only get a couple seconds to read it.

 

OK i went and got some readings
Orange has 12.00 v like it should
red has 080.0
Green with white stripe has 094.0
black with white stripe has 010.4
tan with white stripe has 024.0
I am not really the greatest at reading the volt meter so I'm not sure what they mean and if they are ok so bear with me.

 

Where is the fuel pump relay?

 

its on the driver side inside motor compartment in the corner on the multi use mounting bracket it has a five wire plug in

 

Key off ;the org should have 12V
Key on ; the green should have 12V for 2 sec ,
If the relay is working you should at same time have 12V out to the pump on the tan wire
If you jumper org to tan the pump should run?
If you jumper org to green the relay should operate ( click ) and the pump run.
If the relay doesn't operate consider it faulty and replace it


]

 

Next to the brake booster? Is there anything else in the circuit besides the relay? I know there's a parallel circuit but since it's parallel it shouldn't affect it if the primary circuit is working? You said something about a fuse? Where is it?

Mine stranded me last night and Im getting zero fuel pressure as well, even though power seems to be getting to everything. I always expected fuel pump failure to be a slow, gradual failure, but even yesterday afternoon the fuel pressure was right where I set it.

Vetteoz, thanks for that post, it's helping me too.

 

The only thing between the fuel pump relay and battery is a 20A fuse.

 

First of all, thanks a bunch, that's very helpful.

I have a carbed car, so I run my FP relay off a switch inside the car. The switch is functioning fine, and it just sends 12v through the same green/white wire that the ECM used to send power to. "465" So other than my switch, the circuit is stock.

Im not the best at reading wiring diagrams... but if I'm interpreting it correctly.... If the relay is not switching, then any current sent through the G port on the ALDL port should go straight to the fuel pump. Im guessing it draws enough power that trying to hotwire a battery wire into it is a bad idea even for diagnostic purposes? But I should be able to measure resistance to ground through that port and get a lowish number if the relay isnt switching, yes? And if the relay DID switch (indicating the fuel pump or the wiring between the relay and the pump has failed) then I should have infinite resistance to ground through that "G" port.... right?

The other thing, is that the oil pressure switch sends 12v power from a separate source straight to the fuel pump whenever it's above some nominal psi range... so even if the relay failed while driving, the pump should still be getting power, right? I understand in a cranking situation it takes a while to build up that pressure, but my car stalled out while rolling down the road with great oil pressure so is it safe to assume that even if the relay failed, the pump should still be working?

 

Correct.

So if you still have the OP switch operational you either lost power on the org ( feeds relay and OP switch ) wire or you lost a connection after those two on the way to the pump

 

Probably a dumb question, but what is "the org"?

Do you mean orange wire "ORN 340" on the diagram? Interesting how there's nothing else in that circuit that does anything on my car. No MAF sensor... so there would be no other symptoms as far as I can tell if the orange wire went out. Definitely need to look into that. Thanks!

 

I had a blown fuse (By the battery). It blew 3 more fuses in short order, but now it hasnt blown one in a couple of days. If I cant get the problem to repeat I cant really find it. I have gone around jiggling wires all through the car trying to get it to blow the fuse again.

Will a failing pump blow the fuse?