Fuel guage operation

[ScottnID]

Got a fuel gauage that started acting funny today...

its always seemed to "stick" and then drop considerably rather than smoothly drop as the tank empties, but its hard to say since it has operated consistantly since I bought the truck 5 months ago...

Today, it suddenly went to max full (with over 200 miles drawn down on the tank ~ it should have been slightly ove 1/2) ... then dropped after a while to 3/4, then up to full, and back and forth... all of this on flat level ground at constant speed, so fuel distribution in the tank is not the issue...

At first I figured a short, but I would think that would kill the guage, not send it to max... fuel sender... is there a way to test this... haven't crawled under there yet, but is the sender on top of the tank...?

LOVE THIS TRUCK ~ thank gooddness for the low fuel warning light!

ScottnID

[Southpaw]

Sounds like a fuel sender unit problem. I haven't done this, but you can get to it from under the truck. It is on the top of the fuel tank. You can test it with an ohmmeter. I believe the resistance should be 15ohms at empty and 165ohms at full. Hopefully someone with a little more first hand knowledge will chime in here, but that is what I remember.

Mine has been stuck at full for 2+ years now, but I know mine is a stuck float from boosted launches at the dragstrip with a full tank
Yours is a little more erratic problem, probably the fuel sender. If it is bad, try a junkyard for one. Ford wants $480 for a new one here.

[freeride707]

mines been stuck on full since i got the truck. your lucky you have a low fuel light that comes on... mine doesnt have that, ended up runnin her outa fuel the other day

[tubular031]

drop the tank and test the sender. While you are in there do the harpoon and hutch mod. well worth it if you are taking the tank off.

[ScottnID]

Thanks all!