bluebird71

iTrader: (54)

I have returned my 2000 T/A back to stock to sell and now I need to pull the modified dual fuel pump setup out and swap in a stock setup. The problem is that I didn't install this setup myself so I'm not sure EXACTLY what was changed or modified (lines and wiring). I have a basic idea of the setup: it uses the stock feed line and thd evap. as a return and the second pump has it's own independent relay somewhere. I just need know EXACTLY what wires to swap around or exactly what lines go where stock so that everything will run as it should.

Here is the basic DIY method he used:
https://ls1tech.com/forums/fueling-i...ick-cheap.html

bluebird71

iTrader: (54)

Here are a few pics I took the other day:

Here is the pump itself and I'm pointing to thd added braided line that I believe is the return


Here is what I believe is the ground for the second pump


Here is the other end of the braided line that connects to the stock hard line under the car. There is a stock line hanging down that I believe is the other end of the evap. You can also see where that new ground connects.


On the left of all that, you can see this relay, but I don't know if it's stock or added


What I'm wondering is that if that evap line goes back on the stock hard line at the bottom of the car where the braided line is connected now, then what line goes back into that 3rd port on the pump itself where the other side of the braided line is now connected?

NBM-LS1

iTrader: (7)

I'll print out the diagram here for you at work and upload it when I get home later tonight.

NBM-LS1

iTrader: (7)

Pin B (gray wire) is power
Pin C (black wire) is ground
Pin A (purple wire) is signal wire from sending unit to pcm.

Pin D (black/white) is 5v ref. For sending unit.

bluebird71

iTrader: (54)

I guess it safe to assume then that the red and black wires coming up out of the hole in the center of the pump assembly with the black "goop" around it are added on strictly for the second pump then, correct?

Did you ever find those diagrams? I'm having more trouble figuring out what line goes back into that 3rd port than anything else now.

Is this line here strictly a vent tube or is something supposed to connect to it?:


This is where that line goes to at the top of the tank, connected to a plastic piece on the far right:

NBM-LS1

iTrader: (7)

Well the left line is feed.(marked by the F on top of the sending unit) the middle is the evap line. And the right line is the return.

bluebird71

iTrader: (54)

Well there are only 2 hard lines that go to the back of the car so which go to them and what's this open line coming off that white fitting?

Jeff Smith

iTrader: (44)

good inform

Drj8787

I don't remember where I downloaded it from but there is the gm service manuals on line that u can DL i bookmarked the site but I'm on my phone right now it's on my laptop Ill look when I get off work n post it

Drj8787

heres the link for the factory service manuals
https://www.mediafire.com/?40mfgeoe4ctti
hope that helps