Fuel Gage

[2004mountaineers]

I just put 21gallons in the tank, and the fuel gage was reading just above E. Now
it is reading just below 1/4 tank. It should be reading F.
Any advice?

Other questions:
1.My user's manual (pages 176-177) says there is a fuse panel just under the instrument cluster
to the left (driver) of the steering wheel and downward from the steering wheel.
I pulled the plastic panel and found no fuse panel at all. So, what is going on with
that ?
2.On the passenger kick panel it says "FUEL RESET". And, behind the plastic
kick panel is what looks like about a 3/8inch diameter button. What does that
button do?

https://imgdump5.novarata.net/y0juar.jpg

2004 Mercury Mountaineer, 4liter, v6, awd

 

[Sansjob]

I just put 21gallons in the tank, and the fuel gage was reading just above E. Now
it is reading just below 1/4 tank. It should be reading F.
Any advice?

Other questions:
1.My user's manual (pages 176-177) says there is a fuse panel just under the instrument cluster
to the left (driver) of the steering wheel and downward from the steering wheel.
I pulled the plastic panel and found no fuse panel at all. So, what is going on with
that ?
2.On the passenger kick panel it says "FUEL RESET". And, behind the plastic
kick panel is what looks like about a 3/8inch diameter button. What does that
button do?

https://imgdump5.novarata.net/y0juar.jpg

2004 Mercury Mountaineer, 4liter, v6, awd

if the car was running while filling, the gauge will be sometimes be incorrect. turn off the car and restart. it will self correct. if a fuse was blown, it wont work at all.

 

[2004mountaineers]

if the car was running while filling, the gauge will be sometimes be incorrect. turn off the car and restart. it will self correct. if a fuse was blown, it wont work at all.

(It was not filled while running.)

 

[2004mountaineers]

I added 20ounces of Techron fuel additive. In less than 24hrs,
symptoms are cured. I am using my trip-odometer as a backup
for a while until I am certain the gage is back to normal.
Total cost: $18 from OReillys.