Truck left me stranded today... (inaccurate fuel level)

Headed to work this morning when all of a sudden, engine stalls out on me. Pulled over and realized i was out of gas. The problem was, my fuel guage indicated I still had gas left.

When i left my house my Ultra Guage alarm went off saying 20 miles till empty. I looked at my trucks cluster fuel guage and it showed me 1/16 tank above E remaining. Low fuel light was not on yet. I figured i got gas at some point and forgot to update my ultra guage which would explain why it was telling me I was out of gas. Well... apparently my Ultra Guage was right becuse i made it almost exactly 20 miles when it stalled.

Added roughly 2 gallons from a gas can and headed home. The needle did not change from its 1/16th position.

I went to the gas station right now and filled up. I added 21.26 gallons just now which is more then the tank supposedly holds lol. Meanwhile, I still showed 1/16 remaining when i began fueling up and no gas light. After fill up, my needle went all the way back up above the full line like it should. For now ill track mileage, fill up more often, and use my UG for gas level, but any ideas what could cause the needle to not go less then 1/16th?

Its not stuck because when i shut the engine off the needle drops down below E as it should. It has full range of motion from below E to above F. I feel like its a sensor issue but have no idea how this truck gets its fuel level data. Any insight on things to check?

Here is a pic just moments before putting over 21 gallons in the tank:



All other guages work fine. No CEL (and yes it works). No other known issues. 2009 DCSB 4.0 Prerunner. 117520 miles. All maintenance up to date.

TIA

 

The sensor in the tank is nothing more than a variable resistor with an arm and a float. It may just have gotten stuck.

 

Weird. My gas light comes on at roughly the same position. If I fill up as soon as the light comes on, the truck usually takes 17 gallons to fill back up.

Maybe the float sticks? Or is going bad and there is a dead spot in it where the resistance doesnt read correct?

 

Similar to like the float usedin a toilet tank? I'll know after this tank if it was just a fluke or if the problem is consistant

Yeah my light usually comes on there as well and thats when i fill up which is also 17-18 gallons. Just this time it decided to not turn on.

So if this resistor if bad, does anyone know if it requires dropping the tank to replace?

 

Any chance the light is burned out?

 

Nope definitely not. I think has it dropped just a hair more it would have turned on. But for some reason it thinks i have more gas then i do. Im guessing this float thing was stuck or more likely the resistor or sensor is going back. Trying to find part numbers and diagrams now

 

Same thing happened in my 2010 last year. Stalled out while I was driving on the highway, but the gauge still showed about an 1/8 of a tank, maybe sightly less. Ended up having it towed to the dealership because I thought something was wrong. Turned out I had run out of gas, but the gauge made me think I still had a little left. The dealership replaced a "fuel level sensor" which may be the resistor you guys are talking about. I also ordered an aftermarket fuel pump and had it installed later by a mechanic from an offroad club that gave me a good deal.

Turns out when it was at the dealership they discovered I had a timing cover leak, so they replaced a bunch of seals and gaskets under warranty, so it didn't turn out that bad.

But having had the same issue, it's probably your fuel level sensor (float?) that is giving false readings.

So either A.) fill up early and often, and it will *Probably* be ok, you'll just have a false reading when it's low. Or B.) replace the fuel sensor and if you chronically run the fuel to E like me, you might consider replacing the fuel pump. Something I read about the pump being cooled by the fuel, no fuel = no cooling.

 

@Jerez fault. Faulty gauge swap.
Seriously either the float is sticking or maybe sign of fuel pump going south. When I had a Silverado my fuel gauge started acting funny right before the pump went out. They are both in the tank. good luck.

 

When you put the needles back in you have to set them a little bit lower than you think. Mine kept rising slightly when I tired to put them in how the should look

 

Guages haven't been removed since 2009 when i did the led swap, so the alignment is surely fine. @Jerez is clear on this one lol

 

Can you put a pic of the whole gauge cluster?

 

Yup Rod is a perfectionist when it comes to that. Mine going strong for a few years now as well

 

Also, I just want to state, you've side tracked me, I came here for something else. But now I can't remember.

 

On my trip I've noticed my gauge reading differently.

Since brand new, i would get up to 60 miles before the gauge dropped to indicate full. Then sometime's up to and over 200 miles by half tank, then it would seeing all the way to empty over the next 80-100 miles.

But lately it's been reading more linearly (since about 55k, currently 59k). Still gets the same mileage and miles per tank, the gauge just reads more like it should've since new.

 

weird, i always just fill up when it reads 1/4 tank to never have those issues lol

 

Ill try to remember tomorrow. My camera on my phone is cracked so my pictures come put really hazy and cloudy right now. Ill have a new phone Thursday but just advanced warning the picture will kinda suck

 

This apparently is what i will have to do going forward haha.

 

You're risking destroying your fuel pump prematurely if you run it that low all the time... Remember, the fuel pump sits in the gas tank and is cooled by the gas. I try not to go below 1/8-1/4 tank. Fuel pumps are a pain to change.

 

That sucks. But on both my folks '99 tacoma and my '05 I have noticed an inaccuracy in the fuel level reading. My folks truck will read E and still have 3-4 gallons in it and their light stopped working many yrs ago and I have not bothered to fix it. Mine light will come on at roughly your gauge position and I'll fill up and only get about 18 gallons. I buried the gauge so it pretty much split the "E" in 2 and I filled about 20 gallons. Have no clue why my light comes on so early every single other vehicle I have owned when the light came on I had about 30 miles or so before I ran out or approx. 1 gal in the tank.

 

Analog gauges are not going to be as accurate as an UltraGauge. A lot of the time, gauges show a close estimate of actual values.