fuel guage doesn't always go to full after filling up

[kmartin]

I have a 2004 Ford Explorer Sport Trac about 94,000 miles. The fuel gauge doesn't always go to full after filling it up. It remains at the level where it was before filling up and as you drive it shows its becoming emptier as the low fuel warning keeps going off. After a while, it goes up. Yes, the is the same vehicle that has the hard starting on E85, but this starting occurring before I used E85 in the vehicle.

 

[rmcalis]

I occasionally had that problem with my '05, but not often enough to worry about fixing. Seems to me that it was kind of a problem with Gen1s, especially if the tank was near empty when fueled.

 

[gtyates]

My '05 does this on occasion as well. I have noticed that if I leave the key in the ignition it seems to be more likely to happen. no idea why. After a start-up or two the gauge goes back to normal. Our '04 Explorer has also done this a time or two.

 

[Turdle]

 

[firefly1246]

I had the exact same issue with mine. I ran a whole can of seafoam in the gas tank and improved it. I have since run a can every ~3k miles. There must be varnish build up on the fuel sending unit.

Good luck!!