This just starting happening after having 4 new tires installed in Nov. While I know that can affect mileage (roll resistance, new tread, etc..) that sounds coincidental.

I use the trip mileage indicator as I have sometimes needed to add 15.x gallons to get a full tank. Also, noted when full the needle may be higher above F then it used to be. Is that normal?

I was searching and found it could be the fuel sending unit. Is it more common for the 4th gens to have a bad f.s.u. or just a burnt out indicator bulb, or ...? If the f.s.u was bad wouldn't the gauge reading be way off??

 

If the low fuel light doesn't come on when you first turn the ignition on then the bulb is burned out. Cost $5 at dealer. On 6th gens the low fuel light is a whole different circuit then then the guage. I'm not sure on older models.

 

Hmmm, I never remember that light turning on when starting the car even when I know it did work.

 

Same here. Mine must have been out when I bought it, along with the clock, ODO lights...