My fuel gauge is stuck reading 100% full, which i know its not. the problem arrived after some work last saturday on the truck...I changed the oil/filter, fuel filter and added Gummout fuel stabilizer with a fresh new tank of gas, well this morning it reads full, last night it read 3/4 tank...so i drove 2 hours back up to school and it still reads 100% full. Somethings not right...any help would be great...am I looking at a fuse issue?....Gauge broken?.....NOTE-the truck is a 99' with original gauge cluster...its stock.

 

Mine used to do that...after i sunk it.

I figured it out to be filling the truck up with the engine running. don't do it, it causes a low voltage signal to your fuel pump when the gas pump "clicks" off, I got a CEL otu of it too.

Solution, i don't fill up with the engine running anymore, i have no problems with it anymore

 

Sounds like the fuel sender, mine went out on my Mustang, except it was reading empty all the time.

 

Your sending unit is out. Either drop the tank or pull the bed, pulling the bed is usually the easier route.

 

Ok, thanks...but do you think this is a do it my selfer or do i need to take it to a shop...any price on the damages?

 

Is it throwing a CEL? I wouldn't automatically assume that your sender is bad...do a few of the diag tests to see...

It's a bit of work and a bit of time...and money, so don't go throwing parts at the truck. Try what I said first, it took me 10 resets (starting/stopping truck) for the CEL to go off, and the fuel gauge to function. Mine got a ltitle too wet...

 

Ok, so i should start and stop the truck a bunch of times until it settles again...? and reads an accurate reading...I'll give it a try, um also whats a CEL....sorry im stupid with these things. Thanks for the help though, I appreciate it. I'll post if it fixes itself.

 

Check engine light, is it on?

You don't have to stop/start it a bunch, just turn the key to the on position, wait about 10 seconds, then off. Do it at LEAST 10 times. Thats what got my check engine light off. Please tell me if it works.

And don't fill your truck up with gas when the truck is on...it sends a low voltage surge to the pump...thats all that happened to mine. It works perfect now.

 

Ok, i wont turn the engine on and off abunch of times. I'll just turn the key till the fuel pump kicks on. Dont worry i wont even get a chance to tinker with the truck till saturday or sunday since im bogged down with home work right now. I'm a freshman engineering student and am just beginning to realize the hell of engineering. But no the fuel/ nor engine light is on. Ill definitely post what happens...if it fixes itself or what.
Ya also...i've never filled the truck up while it was running...but i've only had it for 2 years now...so i've only been driving it for about 5,000 miles, who knows what the other owner did? He seemed to take care of it, i mean the trucks still in great mechanical and exterior condition. But who knows....hey thanks for the help again.

 

Well if your not getting a CEL, it just may be the sender itself. It's not too bad, but it's still involved...

 

so i tried to start and stop the fuel pump(turn key on and off) a bunch of times and no luck, the qauge was getting random readings all over the place with no pattern or anything. I must have turned it on like 20-30 times. So it went once to a somewhat normal reading and then after i decided enough was enough and ran the truck the gauge went back to reading 100% full again...what you think? Its going to need looked at by my local mechanic I'm afraid...

 

He's just going to replace the sender...might as well do it yourself.

 

I had an issue on my 99 wire the wiring chaffed the bottom of the cab causing the sender to read way past full. This was a short to power.


It would read full then what it should be. After that it started blowing fuses.

 

Alrighty, thanks for the input fellas, im going to look into fixing the sender myself, um but i checked and theres no wire shorting to the fame or anything...

 

Ok so finally i got it fixed...well all it was is sulfur buildup on the fuel sending sensor...so 122 dollars later at the shop and walla its fixed...but all i had to do was put techron cleaner in it....oh well!