85 FB

1985 GSL-SE

Okay, I have figured out what is going on with my fuel gauge now. I have confirmed that the new sending unit is exactly the same as the old one (no bending the arm required). Now, when my key is in the ON position, the fuel gauge will read correctly. However, once I start the motor up, the needle begins to drop. After learning from another post, I now know that the fuel pump comes on only when the engine starts.

So, the fuel gauge reads properly when the key is at the ON position but doesn't once that fuel pump turns on. Obviously, both the fuel pump and the sending unit share either the same power wire or the same ground wire. Why else would the fuel gauge not read properly?

So, I crawl under the car to find that fuel pump, and honestly I couldn't find it. I follow the fuel hoses from the tank and couldn't pinpoint it. What I thought was the fuel pump didn't appear to be it, plus I didn't see any wires leading to it.

Anyways, where's the fuel pump located, and what wire (power or ground) would be the culprit? I'm going to browse through the FSM and Haynes manual, as well. Hopefully, someone can help point me in the right direction.

Rogue_Wulff

This may sound stupid, but check the negative battery cable where it meets the strut tower.

85 FB

That area's pretty much clean and sprayed down with some Electra-Motive spray, but I'll double check it anyways as a precaution. Any other suggestions?

Rx-7Doctor

iTrader: (13)

Your fuel pump is located near the left rear wheel along the frame rail. The fuel filter should be attached to the outer housing where the fuel pump is located underneath that steel undershielding.

85 FB

Are there wires running into it? Because I could not see any wires along the frame rail.

FBsliderseven

iTrader: (2)

there are wires.
btw the fuel pump is located up a shield like the doc says so the wires would be hidden.

85 FB

Would that shield be white in color and mounted against the framerail? Because, I did see something like that with a couple hoses running in/out of it.

Rx-7Doctor

iTrader: (13)

If it is white someone painted it but you are in the general area. You can't see the wires because the run into the driverside storage bin. If you remove the bin, underneath is the wiring for the fuel pump.

85 FB

Thanks a lot, I'll keep that in mind. The shield was white in color, but that could've been because of the type of dirt and debris and whatnot spraying up against it.