It wont prime, it wont start. The fuse is good, the relay is good. What else is there?

 

Is there power at the pump itself? What about a good electrical ground?

If there is power at the tank connector, you'll probably be looking at a new fuel pump in the near future.

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Later,
Vader
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"Let the bodies hit the floor!"
Adobe Acrobat Reader

 

I went outside and tested the connections above the differential, only the middle one is getting power. What does that mean?

 

Ummm the middle one is the pink wire right?

If I remember right that is the one for the gas guage. That should always have power to it.

To check the main power line going to the pump ya gotta hook up your VOM to the 2 outter prongs then have some turn the key. What happens is that the relay on engages for a few seconds to prime the pump then it shuts off cause the ECM sees that the engine isnt starting so it kills the power to the relay.

Because of that, that is why you only saw power at the middle connector.

Try what I said and i am sure that you'll have power to the 2 outter prongs.

Kat

[This message has been edited by Kat (edited June 10, 2001).]

 

Rezinn,

To verify the operation of the fuel pump, install a jumper from the 'G' terminal on the ALDL to a 12VDC source. The pump should run as long as teh jumper is in place. Make sure you use a 12VDC source that is fused for at least 20A, like the CTSY circuit that operates the cigar lighter. It would be really easy to fabricate a power cord to adapt the lighter to the ALDL terminal (it works for me).

With the 12VDC supply connected to the 'G' terminal, you should either get a running pump or at least be able to troubleshoot the power at the tank connections.

------------------
Later,
Vader
------------------
"Let the bodies hit the floor!"
Adobe Acrobat Reader

 

I had the key turned when I tested the wiring under the car. On my car the innermost(left) relay says "MAF POWER" in red letters, I didn't even change the fuel pump relay.. I changed the one on the far right(MAF burnoff, apparently). So I guess I need to recheck the relay. There are 5 or 6 wires connecting to the relay, which should have power?

I will test for power at the relay and the ALDL, thanks for the help.

 

Well, the fuse is getting power, I cannot use the ALDL for some reason. Connecting terminals A and B does not even put the computer into diagnostic mode. Im thinking my computer got fried? But wouldn't connecting power to terminal G still make the fuel pump run? Which is terminal G? I counted ABCDEF-G from the right top but there was no connector where I ended inside of the hole(NO metal piece to make contact, like inside terminal A). Argh, help

 

I understand what you're saying. The schematic on my 1991 service manual for the ALDL does not show anything being connected to terminal "G". Perhaps not all years used it.

Further, check out the post made today that I responded to at https://www.thirdgen.org/messgboard/...ML/001664.html in the electronics section under NEED HELP REAL BAD GUYS!!!! for a discussion on testing the fuel pump. I think that it will be pertinent to your problem, including detailed instructions on how to test it.

 

Thanks Stuart, Im going to look at this..

 

What does it mean if I cant jump terminals A and B on the ALDL to make the computer run diagnostic mode?

I looked for a hanging red wire by my passenger side strut tower, there is one that shares a connection with my accumulator.. And another above my ignition coil. The one closer to the strut had about 5 other wires in a connector with it.. I looked through my manual but I couldn't figure out what to do, I think Im done for the day.

 

Rezinn,

This is the ALDL layout:



It is arranged "backward from what you might expect, but the mating plug (from the diagnostic equipment) is arranged "correctly" if you view the end of the plug.

------------------
Later,
Vader
------------------
"Let the bodies hit the floor!"
Adobe Acrobat Reader

 

Hey, anyone happen to know this: I just need to run a hot wire to the fuel pump to see if it's pumping, which of the 3 wires going to the tank is the hot for the fuel pump??