My xfs sat during covid. I started it and went on quick trips but always less than 5 miles and some weeks not at all. First time I took it out and the thermostat blew up. Yes, BLEW up. I filled it with coolant, thought that would be the end of it but before I got home....boom. steam and coolant everywhere. Got it home, replaced the thermo, still leaking. Replaced the water pump, exchanged curses with my closest dealership parts guy, finally got the right hose and now I'm all set. Only now my ECO doesn't work and my gas gauge says 0.0 miles. Went to put some gas in it to prove I wasn't crazy (i knew I had put gas in it before the thermo incident) and now it's creeping up to 0.6 after 5 gallons. Odd thing is, the line gauge under the digital gauge is reading accurately, just not the numbers Does anyone have any ideas?

 

What's a gas gauge? Do you mean the number of miles you can drive on the remaining tank? If so, what does it show when you fill up the tank?

If you've only done short couple of mile journeys for a while (burning lots of gas while the engine warms up) then the average fuel efficiency which it uses to calculate that will be very poor. So that might be why it doesn't think you can get a lot of miles from what's left in the tank.

 

Yes, sorry for the confusion. The remaining miles left in tank. This isn't a low average because I've not driven it, it dropped to zero when the day before it was reading 100+ mile's in the tank. The bar at the bottom also dropped to zero but only started reading correctly after another trip to the gas station.
But what you say makes sense. Although I've never seen such a drastic difference from one day to the next.

 

The issue is a poor connection on the wires internal to the combined in-tank pump and level sensor. You'll need to access the pump under the rear seat - see attached TSB for fix. Heads up: the locking ring for this unit can be TIGHT - many have reported having it off as you'd expect with a hammer and chisel/screwdriver, but mine required the special removal tool, plus a 3 foot breaker bar and an additional few feet of cheater pipe to break loose. YMMV.