I have 2000 Ranger XL with the 2.5 and the fuel gauge is stuck well above Full. Disconnected the battery and the connecter on top of the fuel tank and it hasn't budged. Any helped is appreciated

 

Ford fuel gauges, 1989 and up, use 16 Ohms(Empty) and 158 Ohms(Full)

Ohms is resistance, 16 ohms almost no resistance, like a short, a direct connection

High ohms(158) is like no connection, disconnected wire.

So below Empty would be a short, assuming tank isn't empty, lol

Above Full is a disconnected wire.

Battery would not effect this in most cases.


Some ideas here: fuel gauge over full - Ford Explorer and Ranger Forums "Serious Explorations"®
Read it all the way thru

The wire for the gauge at the tank end is usually Yellow.
If key is on and you Ground the Yellow wire, 0 Ohms, then gauge should go down to empty.
If that happens then gauge and yellow wire are OK most likely problem is the Sending unit(float) in the tank or its Ground wire.

Gauge----(yellow wire)------------sending unit(float)----------Ground

 

Ok thanks, I filled up and only have driven 100 miles. Going to wait till I'm closer to 300 miles to drop the tank, just so it's easier

 

You can use a sewing pin to pierce the yellow/white strip wire in the harness(frame area), then ground the pin with a jumper wire, and see if gauge drops down to empty, it should if wire and gauge are working, key on for that test.
That would tell you if you need to even drop the tank.

 

Sweet.....kinda. Did the needle in the wire and grounded to frame and shot straight to empty, will be dropping the tank soon, hit 150 miles so once it arrives I'll get it in and be ready to go

 

Also look at taking the bed off.

6 bolts and the tail light wires.

Filler tube needs to come off for either method, bed off or drop tank.

With bed off, or just moved back, all the tank wiring stays in place so you can see if there is a problem, it is best to have a helper to move the bed off and back on.

Google: ford ranger bed removal

Lots of info on that

 

I'd have to just scoot the bed back since I don't have any help around

 

Probably too hard for one guy without some sort of lift, don't want to damage the bed.

I had rusted out rear leaf spring hangers, but had a garage.
I backed truck in and use straps and come alongs to lift bed up via rafters, then drove it out to do the work.
Realigning was harder but bed isn't that heavy.

 

I'm surprised at the lack of rust present on my truck, hardly any on the frame and all the nuts and bolts are still silver

 

of course i happen to have everything to drop it and the only thing thats fighting me is the 2 hose clamps on the fill neck, the bolts on the tank straps had 0 fight lol

 

got the bed back enough to drop in the new assembly...almost stripped out the one bolt behind the driver seat but got it out. not too hard and its all together and working.
the hardest part was that my impact wasn't getting them off but i got em off with a breaker bar lol

 

Bed bolts?

Good work on getting it fixed :)

 

yeah the bed bolts, that wasn't fun lol.

 

Rather then start a new thread...

Grounded the yellow (and white) wire through the frame, and the gauge went straight to empty.
I also used a Black wire with an orange tracer as the ground, and also made the gauge go to empty, the black/orange wire is the ground to the gas sender unit anyway.
There is also a thick black wire and that also worked as a ground to make the gauge go to empty.
Doing a continuity test to the frame to these two ground wires shows no resistance.

Still the problem persists, sometimes the gauge will show full, other times it shows 3/4 full _ which is accurate as I could see that in fact the tank is 3/4 full.

I pulled the fuel relay and hooked up the sender unit to the gauge and moved the float by hand to "EMPTY" with the key on, and it did not come off of "FULL" until I turned the key off and on, then it moved to "EMPTY"
The gauge doesn't want to move when I manually move the float.
I even held it there for a while and the gauge refused to move until I cycled the key off and on.

I'll have a look at the gauge and its resistor and the anti slosh module unit that I've read about.

It just started doing this out of the blue, I was driving and noticed the gauge went right to full.