Gas gauge not working

[N3LRX]

The gas gauge in my 93 Explorer is not working it stays pegged way beyond full all the time. The only time it moves is when you first turn on the key it goes down for a bit then pegs out again past full. I haven't run out of gas in it yet but I haven't taken it on any long trips yet either.

Does anyone know how the gas gauge works is there a computer involved or is it just a simple float and gauge design?

 

[Zepplin454]

it has the old fashioned electronic floating lever sending unit. the guages do a test to see if they are working everytime you turn the key on. but you probably have a bad sending unit. best to buy a ford part not a aftermarket part. aftermarket has more problem and dont rebuild it it not worth the time in the long run. i would also check for broken wires near the tank and on top of the sending unit

 

[Dbovill21]

The gas gauge in my 93 Explorer is not working it stays pegged way beyond full all the time. The only time it moves is when you first turn on the key it goes down for a bit then pegs out again past full. I haven't run out of gas in it yet but I haven't taken it on any long trips yet either.

Does anyone know how the gas gauge works is there a computer involved or is it just a simple float and gauge desi

 

[Roadrunner777]

Pegged full is unusual, they usually fail the other way. In essence, yes, it is an old school design, variable resistor on a float in the tank and an analog gauge. The only complication, and I think this might be significant in your particular case, there is an anti-slosh module in the gauge module, keeps the gauge settled down.

Anyway... honestly, I love fuel gauge issues because they are relatively simple to diagnose. But, I simply cannot bring myself to type through the diagrams and procedures for what must be the 10th time. Please... scroll to the top of this page, Click Search in the upper-right corner, type 'fuel gauge' and choose 'This forum' from the drop-down if you appears (optional), then browse the first 30 or so results. I absolutely guarantee what you need will be there.

 

[Cheddar_Dan]

Yeppers! With key off my 1994 gauge shows 1/8 tank of fuel. With Key on gauge bottoms below empty "red-hash". No doubt it is being instructed to do so.

 

[RangerX]

Sharing this link, not sure if it would show up in a search due to being in an archived section Ford Explorer Maintenance Tech Tips Service Problem Solving Repair
Scroll down to the fuel system section, lots of good info. Lots of good info in the other sections too, valuable 20+ year old writeups for gen1s.