Power to pump, but it will not prime.

[EThirty318i]

Before we get started...

I have searched for about a week now and haven't really found anything.

Car: '91 318is
motor: '94 525i m50tu
Stock harness w/ akg adapter.
the harness is hooked up correctly, I can jump the fuel pump relay (pins 30 & 87) and nothing happens.
I checked for power at the pump on the 3-prong connector, power is going to the pump but it will not prime. I know the fuel pump relay is bad, but having a jumper wire should cause it to prime regardless of the key position. I was told by a few people the relay itself might not be grounding, or the pump itself.

I checked the voltage at the relay, w/ the relay installed I get unsteady reading, w/o the relay and a jumper wire, constant 12v.

I have no clue when it comes to electronics. Anyone have any suggestions?

Thank you in advance!

[iansane]

Maybe I'm missing something here but if you have power directly to the pump, and it doesn't do anything, then I'd be guessing the pump is bad...

[Oz10]

Do you have spark?

I'm thinking maybe something is keeping the pump from switching on even though it has power.

[EThirty318i]

I'm not sure on spark, The crank/cam positioning sensors are brand new and I was told that they should be getting spark.

iansane: True, that was my first thought, however I pulled the tank out to redo some gas lines and while the tank was out I used a battary and some jumper wires just to check and make sure it worked. First time I was feeding the pump backwards, so i switched the wires and it shot out fuel.
So i dont think it would've gone bad within 2 hours after that.

I think I saw where someone just got a new pump and it worked but thats another $200

[iansane]

How is the pump grounded?

[BenjaminButtton]

You said the harness is hooked up correctly?

I would maybe check out the AKG adapter, I've heard some people have issues with them not being hooked up quite right. Just a thought.

[328ijunkie]

The 3 pin connector is for the fuel level sensor. The FP is a 2 pin...

[EThirty318i]

well, I completely feel like a dumb ass after that... went back home for a few hours today and didnt get to do a lot. I installed the new fuel pump relay, and everything but had left my multimeter at my place in VA so couldn't find out if the pump was getting power.
My main relay now clicks really loud.

I'm completely lost as to what it could be.

[EThirty318i]

Main relay now clicks really loud after I installed the new fuel pump relay. Still doesnt prime but will crank.

WTF?!

Does anyone have an idea??

[ryanc88]

I would start by checking the agk adapter. make sure its all wired up correctly and that all wires are there. then clean and check grounds. also the power block on the passenger side firewall how do you have those hooked up?

[EThirty318i]

I checked the plug for voltage and got nothing. So, as ryanc88 stated I will check the akg adapter. I even added jumper wires and the pump primed, but when I went to crank it nothing happened? So I guess the next step is checking the akg adapter, then making sure I have spark. I know the crank sensor is ohm'ing out within spec and the cam is as well.

Anyone know of someone else with a similar problem??

[ryanc88]

I had a similar problem, i put the power wire from the harness to part of the block that isnt getting power (from the block) and it took me for ever to figure it out. thats why i was asking about how you have the block wiring set up. ill go take a picture of mine real quick for reference. but definitely go over the adapter and grounds. then hopefully youll be good to go.

[ryanc88]