Gas gauge

[patrick84]

Does anyone actually HAVE a functioning gas gauge in an early Ranger??? All the other gauges work fine. We've had the bed off the truck once, and tried to get the gauge working while the bed was off. Pulled the sending unit, cleaned the contacts, reinstalled it, and the gauge barely moves off "E" now...and YES, there is plenty of fuel in the tank!

Anyone have a solution here? Thanks!

 

[RonD]

Google: Ford anti-slosh module

At the gas tank there will be a Yellow/white stripe wire, that is the gas gauge wire.
The sender in the tank is a variable resistor, connected to a Ground, the needle on the gauge shows the resistance to Ground.
Pre-1989 Ford gauges used 73 Ohms empty and 10 Ohms full

Ohms is resistance, 0 ohms is no resistance, direct connection.
Higher ohms is more resistance.

So if you disconnect the Yellow wire gauge would show Empty, below empty, no connection, no connection is the same as a gazzilion-million Ohms .

If you Grounded the Yellow wire it would be 0 Ohms so gauge would show Full, well over full, no that won't hurt it.

If gauge needle doesn't react this way then the problem is in the dash board.

1989 and up Fords use 16 Ohms empty and 158 Ohms full, so opposite of early models

 

[kimcrwbr1]

Ground the sending unit wire to a good ground with the key on and the guage should read full. If it does the ground to the sending unit is bad or the sending unit itself needs replaced. Have you tried slapping the dash above the guage cluster it could also be a dirty connector?

 

[85_Ranger4x4]

Mine never reads consistant, it can be half a tank, 3/4 of a tank and a quarter of a tank in the same day. If you go the average it will give you a rough idea but not very accurate.

It plain sucks you can't get a sender for a carbed first gen. I was going to pick on the stupid thing when I have the bed off for bodywork in the probably somewhat distant future and see if I can get something to work.

I just go off the trip timer, been working decent for 15.5 years so far...