Fuel guage

[MUDSTROKIN']

So on my lunch break i stopped to put in some diesel since i was down to a 1/4 of a tank. Put the nozzle in started it up and got back into my truck, Watched for the needle to start to climb and after a couple seconds it didn't? so i looked to make sure it was pumping and i had 7 gallons in, kept watching the needle and nothing, I put in 20 gals and no move in the needle, got back to work shut it off and turned the key back to koeo the guage was still on 1/4 tank. Anyone know whats going on? the only thing i can think would affect it is on my way out some idiot in front of me who wasn't paying attention slammed his brakes and i had to slam mine and came to a pretty hard stop. But other than that im clueless

[howell_jd]

I had a "lazy" fuel gauge last year. It was the fuel sending unit. It had gotten wet (from fuel) as I had a crack in my Transfer Flow fuel tank. I had to replace the fuel tank but not the sending unit...I've had no problem since it has not been subjected to the wetting.

I don't think the 2005 Ford F-250 had a 40-gallon behind-the-axle fuel tank but Ford Doctors has an article:

Diesel Technician Society

Hope this helps direct your troubleshooting.

Good luck!

Jonathan

[MUDSTROKIN']

I don't have the behind axle tank, could this still be my problem? what do i need to do check my tank for cracks?

[howell_jd]

If you had a crack in your fuel tank I think you would know it. The crack in my tank was very small but a drip even every few seconds makes a fairly large slick underneath over the course of a day. The top of the tank is where I would look for signs of wetness. It could be wet from accumulated debris not necessarily fuel. Another way to check for sending unit function is to use a voltmeter on the backside of the fuel gauge (I would imagine a lower voltage reading ) or to query the fuel tank through the OBDII port (likely to report a percentage full not a gallon figure).

When this happened to my truck, there was an associated DTC as well: I think it may have been P0460 but I am not certain...I cleared it out from the keep-alive-memory after the problem went away.

You may find the OBDII guide from MotorcraftService.com helpful too:

http://www.motorcraftservice.com/vdi.../DOBDSM502.pdf

(the link is for 2005 Fords with the 6.0L diesel)

Check for DTCs and see if that helps direct your troubleshooting. Good luck!

Jonathan

[MUDSTROKIN']

Thanks Jonathan!

[ford diesel]

mine does thas all the time on my 2000 and my 2005. turn the key off an back on usually fixes it.

[MUDSTROKIN']

^ i tried this when i got back to work and it didn't fix it