gas gauge question

[john112deere]

Using a 2009 F-150 today at work. Pretty standard work-truck- 4x4 XL, auto trans. Not assigned to me, but I use it some.

Had just over half a tank of gas. It's a big tank, too- will take about 30 gallons, I believe. I parked the truck, idling, with the nose pointed downhill for maybe 10 minutes. Not a real steep grade- 10-12%, I guess.

Got back in, and the dash was flashing about low-fuel- 35 miles to empty, I believe it said. Greg said it's done the same thing before when parked nose-down.

We stopped on flat ground, shut off and restarted. Still reading nearly empty. Tried sticking the stupid little funnel in the capless filler neck, and restarting.

Drove it home (more than 35 miles) and the gauge was very slowly coming up over the course of that trip.


I'm OK with leaving the truck on a hill giving a wonky gauge reading...but I don't get why it didn't reset when we shut the thing off and restarted it. Any thoughts?

Truck's got some miles on it (72k, I believe), and was hit pretty hard in the back end while parked earlier this year. Gauge seems to work fine under any other conditions, though.

 

[smokey]

My cars do the exact same thing. Annoying to say the least.

 

[Blue Goose]

When you shut it off, did you just shut it off and re-start it, or did you get out of the truck for a while?

 

[john112deere]

First time was under a minute, but then we stopped at a store long enough to buy coffee and candy for the ride home- several minutes, anyway. Longer than you'd wait after, say, filling the tank- and the gauge jumps right up when you leave a filling station.

*I've driven something, somewhere along the way, with a slow gas gauge float- wouldn't read full until four or five miles out of the gas station. This doesn't act like that, either.

 

[smokey]

It has to do with the fuel slosh circuit in fords that keeps the gauge from bouncing around. My Escort and Focus does this when parked on a steep incline. It does it mainly if turned off but had happened while running.

 

[john112deere]

Could've sworn that circuit reset on the key cycle, though.

Either I'm wrong, or they've reprogrammed the algorithm since 1997. Either is entirely possible.

 

[smokey]

The Escort is a 2000 and the Focus is 2009

 

[john112deere]

Same thing again today. There is something wrong with this truck.

I've driven a fair number of Fords over the years- my two Rangers, a '98 Escort, Dad's '00 and '07 Focuses, Mom's '94 Explorer, just to name a few- and I've never had one half as screwy as this dumb truck.