2004 Faulty Gas Gauge

I got a 2004 crew cab limited tundra and since I got it my gas gauge will semi work usually seems accurate till around half a tank when it will sit towards a quarter to just fully empty. It used to just go all the way up and then back down again while I would drive but now just works till about half a tank. Hopefully that makes sense.

So my question is, is that a bad sending unit, float or what?

The gas light seems to work, kind of flashes or just stays on for a minute then turns off. I don't know if that helps or not or if that's normally how it shows.

 

Try smacking the bottom of the tank right around the middle of it with a rubber mallet or a piece of wood. If there's something stuck on the float, it MIGHT knock it loose and get you a proper working gas Guage again.

 

Or your Guage in the cluster is going bad

 

I'll try that, thank you. Ill let you know if anything changes.

 

I’ve got a similar problem but the bottom quarter mark is more like 2 gallons to empty vs 5 gallons the way it used to be originally. I need to fill the tank to really figure what was used.

 

Exact symptoms of a faulty sender. Best way to be sure would be to check resistance on the sender wires when the gauge is reporting empty.

This happened to another member, I told him the same thing, he confirmed. I can dig up the thread if it helps.

 

How hard is it to access the sender wires? Like is it behind the dash or do I have to drop the gas tank?

 

Check this thread and see if it helps.

https://www.tundras.com/threads/fuel-gauge-acting-weird-where-should-i-start-looking.110955/

EDIT: I can't remember if @Aerindel is the one who actually pulled the fuel pump and slid the sender float up and down or not, and replicated the condition. Someone here did that. I'll try to find the thread...

 

Still can't find it, but @BubbaW also posts info on how to test the gauge over here: https://www.tundras.com/threads/ran-out-of-gas.105081/#post-2703325

 

I'll have to try that when I finally get the bed off my truck to open up the gas tank.

 

If you're open to cutting wires, the wires for the sender get to the gauge cluster via the driver side sill plate. You'd just need to look at the EWD to figure out which wire(s) you'd need to cut and re-splice. There may be a combo connector you could tap into once that harness reaches the kick panel or dash area also, which you could probe, but again, you'd need to consult the EWD for your year/make/model to know for sure. I have the worst time reading EWD's, BubbaW is king in that territory.

 

That would still be difficult since I can’t physically see the float to gauge whether the resistance is off.

 

You should be able to slosh the fuel in the tank by nudging side to side, and ensure the resistance changes? The resistance should be within a specific range, and should fluctuate when you either jack up one side of the vehicle, or force the gas to slosh. I'm sure they baffle the interior of the tank, but ... you should be able to move the float still.

 

Wasn't me. I figured out I have a dead spot on my sender around 7/8ths of a tank where the needle will just start dropping to zero until I use up some gas or change the angle of the truck. I had pulled my pump a couple months before this issue and gotten a good look at how it works though.

 

I had the same 'gremlins in the gas gauge' problem. Someone suggested a bottle of Techron.
This worked for me.

 

Ill check out those links, thanks for those