ledfootz28

I got a new ac delco sending unit off amazon which includes everything from the bracket the pump sits in,metal fuel lines,harness which is all one unit.
I also already have a access panel above the tank and I noticed when I went to swap out the sending unit the harness on my stock looks like it splits off into 2 harnesses then the main one but the new one just has the one big harness with the white/blue plastic casing.

Anyone ever put one of these in and had to do any electrical work to the new sending unit to make it work.I do have a walbo pump but i dont think these 2 harnesses are from that install that i can remember.Also the harnesses are located behind/below the tank kinda near the rear.

Kevin Blown 95 TA

So does the one you bought have the usual 3 position connector with gray, black, and violet wires - and you can't plug in the connector?

ledfootz28

Yea the new one has one harness wit the 3 wires.I forget what colors they are bc i dont have the car/part with me.the harness is pretty big and its white or clear if i can remember.But when i looked under the car where the harness plugs in it looks like the wires on the stock harness on the car have 2 harness connectors spliced in.

Or maybe I just saw harnesses for something else?

Injuneer

Shoebox has a photo of the fuel sending unit harness connector over the rear axle, showing the wire colors:

http://shbox.com/1/fuel_pump_wiring.jpg

http://shbox.com/1/fuel_pump_connector.jpg

ledfootz28

Yea it seems i have 2 harnesses spliced into the main harness that are located in shoeboxes pic where it says "to fuel tank".Im almost positive its spliced into the sending units main loom but i ll go to the car today and check it out and take pics if I can.

Kevin Blown 95 TA

Did you buy it already modified? It's possible it was set up for an extra relay and bigger wires to get better voltage to the pump or something like a pump booster. Do you see an extra relay or some larger red wires anywhere near the area behind the driver's side back seat or anything that looks added on?

Either way, for your sending unit - violet is the fuel gauge, gray is the pump 12V+, and black is ground. There should still be a connector for it - maybe show us what you took out of there???

ledfootz28

Stupid question but how can i upload an attachment picture to this thread.Usually forums have an upload attachmen option where you post a thread/reply

ledfootz28

Ok heres a link to the pic on my photobucket.hopefully this works.

The sending unit with the 2 harnesses in the pic is the one I took out of the car.the new one with the 1 white/blue harness is the new unit.
Im really stumped here guys!

001.jpg picture by ledfootz28 - Photobucket

I thought maybe i spliced the 2 harnesses in when i did the racetronix setup but the 2 harnesses are from the factory..no splicing.I still however have the big white/.blue harness on the car its just after all this harness bullcrap.Then theres a little black box bolted to the car and has a wire running all the way to the alternator i think for the racetronix setup.

ledfootz28

another weird thing is the harnesses near the pump are a little bigger than the new stock one.So its not like i can just splice these 2 harnesses to the new unit and im good.to transfer the walbro pump the harnesses wont mate up i think.

ledfootz28

The gm part number for the new sending unit is19111412 and AC delco number FLS1031.Im pretty sure this is right for a 94 Z28.
I just cant see how my harnesses look diff than shoebox pic.