86lariat

Got a problem relating to the dual tanks, fuel gauge and voltmeter on my 1994 F150.

I was actually working around my steering column replacing the shifter boot and shifter column bushings. I finished those tasks and put it all back together and noticed my fuel gauge was reading below empty (I had just put fuel in both tanks that day). So i started it up and still reads empty. Switched the tank selector switch to the other tank and still showed empty. Of course I switched tanks several times (which did nothing) but I noticed then that the voltmeter was completely on discharge (8 or so) and would move slightly when I switched tanks. Like on the rear tank the voltmeter showed 8 and when switched to front tank the voltmeter might move down 1/8th of and inch or so, then move back to 8 when switched back to rear tank.

Since I had only been working around the dash area, i thought I might have blown the tank selector switch somehow plugging and unplugging it. But no, I bought a new tank selector switch and tried it, and it did nothing to fix the problem.

The truck still runs on both tanks. Made a long trip yesterday and used both tanks.

Not sure where to go from here so any help would be appreciated.

ttroy350

Sounds like a ground issue. Check the gauges ground

fltdriver

You probably dislodged a wire when doing your repairs, like was stated already check the ground, also anything that you unplugged needs checked to make sure all contacts are still properly situated in the connectors. Spend a little time tracking the wiring from cluster to ensure nothing broke or is grounding out.

86lariat

Thanks guys!. Your posts got me back on track with the problem. I happened to have another gauge cluster in the shop and put it in the truck and the problem disappeared. Then plugged my original cluster back in and it worked fine. So yeah, something in the wiring or plug-in was all it was. Thanks!

fltdriver

Glad to hear.

Mr 242

My truck has 2 tanks and wile on the forward tank I pull up to a shop turn off the engin.
When got back in tried to start, eigin just roll over, check spark "good" went back in and switch tanks and she started, did a check when on a stright road switch back to forward tank and she cut off.
Is there 1 relay per pump, can the change over switch cause this or am I going to have to drop the tank and change the pump.
Need Help

Mr 242

My truck has 2 tanks and wile on the forward tank I pull up to a shop turn off the engin.
When got back in tried to start, eigin just roll over, check spark "good" went back in and switch tanks and she started, did a check when on a stright road switch back to forward tank and she cut off.
Is there 1 relay per pump, can the change over switch cause this or am I going to have to drop the tank and change the pump.
Need Help

Chris_1

iTrader: (1)

No - 1 relay for both pumps. Power goes from the relay to inertia switch, dash switch, tank pumps.
Each tank has it's own hi-pressure pump. The dash switch switches between pumps and sender units.
I'd check the dash switch first.
Then check you're getting power at the pump.