I have a 2004 Lariat with the 5.4 3 valve Triton V8. It's got an interesting problem with the low fuel level indicator. It's more annoying than anything, it doesn't affect performance (at least I don't see how it could). The problem is that my truck will tell me that the fuel level is low anywhere between half a tank and an eighth of a tank. Obviously this isn't a major issue but it takes place of my outside temp, compass heading and MPG indicators. I have to hit the reset button to get that information back. Anybody else have this problem? Other than "living with it" is there a practical solution?

 

GOD! That's a major problem. You need to have that thing hauled off to the junk yard! LOL .

Just kidding. My identical make model does some squirrel y stuff just about like that. Sometime, I crank it up it will read near empty (then LOW FUEL ALARM) and by the time I drive a few blocks it is reading 1/2 tank. Sometimes a tfull tank fillup it indicates 250 miles to empty. Next time it will be 325 or 375. ???? I actually 'THINK' this may be a prelude to having to replace fuel tank level sensor. Which I dread because it is apparently a pretty good job (maybe too big for this ole 74 yr old fart!

 

keep it above a half tank?

 

you're funny. I work 4 days a week and only make tips, luckily I only have a 5 minute drive to work. Some days I don't make enough for half a tank.

 

I'll go out on a limb here....maybe it's you're purge valve....My experience has been with plastic type tanks....
If it is & you have a plastic fuel tank when it's failed it will (by vaccum suck the bottom of the tank upwards) then it will hit the sending unit which then
gives you a false reading to empty...The longer/more you drive the more erractic it gets...
Also a good sign this is happening is you will have a pretty good hissing of vaccum when you open the fuel cap to fill....
Also if you've driven long enough & look under the tank (towards the front) you should be able to see the bottom of tank being sucked up ??

Of course if this is your problem & fix...report back here so others can learn also !!

 

just thinking outside the box...Could it be thr computer adjusting its calculation of fuel economy? I am not familiar with your year of truck, but my 2015 alarms at a certain “miles to empty”. As an example, if the computer calculates you are getting 4mpg one time and then adjusts to 15mpg or vice versa...do you think this would trigger an alarm? Again, I’m just spitballing here because I haven’t owned that year model. Am I making a bit of sense?

Does your fuel gauge change showing low when you get the alarm or just the alarm and your gauge reads correctly?

 

I believe that you have probably hit the nail on the head, I had pretty much come to that conclusion independent of reading your response

No, the gage doesn't change