Hey all! New to the forums. We just bought an '07 with the 5.7 hemi with 87k miles on it and so far we've been in love with the vehicle. However just in the past couple of days I've noticed the fuel gauge is staying at FULL. We filled up last Sunday night and have driven it almost every day since then at least 10 or so miles a day. I may have "overfilled' it but don't think that it would still be considered full. Could that be possible? I first thought maybe it could be the float but most times that would have the gauge show as empty wouldn't it? Could it be the gauge itself? I don't want to go get the pump replaced if it doesn't have to be. Do you guys have any thoughts?

 

The pump would not need replaced. I used to get about 12 miles per gallon in my 2007.
FF

 

try some marvel mystery oil in the fuel. i have heard it MIGHT work. normal dose is 4 oz to 10 gal gas. but i have seen as much as 8-10 oz to 10 gal not be trouble

 

im gonna have to try that marvel oil out. Good news is, looks like we put the cart in front of the horse on this one. The guage is working, the wife just overestimated the amount she had driven that week.

 

Ive had some good luck on my truck with techtron. Put some in with a fairly strong miture and run it for a little. should fix it, but might just be temporary.

 

Techron claims it will fix the electronics in the fuel gauge. I do not see how as it is a gas additive, but I do use it along with Marvel Mystery oil and in my Coronets.
FF

 

Techron helps remove the sulfur buildup which is often the cause for the electronic problems, like the sending unit.