Gas issues... PLEASE HELP!

Hey guys I need some help here. I understand the stupid issue with the fluctuating gas gauge. Got that. HOWEVER my issue isn't with that (so much). Granted, I haven't seen my gauge go over 3/4 in a HOT minute but my issue is the AMOUNT I'm putting in the tank. It started with a solid 10gal and is now down to "shutting off" a little over 7. I just pumped gas so here's the story - I know for a fact I had at least 8.25 in it (I put in 2 days ago!) and my gauge was reading BELOW the E line. So I pump and it shuts off at 7.57. Frustrated, I pulled the pump out just enough to where I could see the gas flowing down the "pipe". It would despence .32 before the gas was bubbling out. I repeated until I reached 10gal. I'm patient, yes. Guys help me out here - WHY CAN'T I GET MORE GAS?! I don't WANT to run it dry but damn. HELP, PLEASE! (Oh and I average about 15m/gl)

 

You say you haven't seen the gauge go over 3/4. Sounds to me that the gauge isn't registering the actual amount. Perhaps the tank is full when the pump stops.

 

If I had the time tonight, I would have stood there and done the little amounts at a time but man, that'll take forever! LOL are there any hoses or other items should be checking in the meantime? The one thing I don't want is to actually run out of gas when I don't intend to! That blows the fuel filter doesn't it?

 

I agree with @moondeath. When the pump stops, leave it at that. "Topping off" the tank by pulling the nozzle out and adding more can cause liquid fuel to enter your charcoal canister/evap system and cause issues that can cost more time and $.

 

There isnt a normal fuel filter on the Tacoma. Overfilling the tank will trash the Evap canister. I don't have any fluctuations with my gas gauge. It stays at the full mark and then starts going down around 60-70 miles.

 

Must be nice to have a functioning guage! LOL ok so assume I go off the "fuel tank is full" theory, and I do run out of gas, what will THAT harm? Is there any way to "check" or fix my guage if it's off?

 

^this

 

The fuel sending unit is the 'float' that sends the signal to the gauge to register the amount of fuel. If the unit is faulty, then the gauge won't register correctly. Which would also explain why you have a gauge that isn't consistent. Only way I know of to check it would be to drop the tank and do an ohms resistance test on the sending unit.

 

I wonder if your tank has a dent. Happened to a Mustang I drove in high school and it cut the capacity by 2-3 gallons.

 

Going off the "tank is full theory" a full tank is 20gal, you say 15mpg so 150 miles is 10gal, (half tank),,
so get in the habit of filling up every 150 miles until you can get the fuel gauge fixed.

As far as running out of gas, the fuel pump is in the tank and uses the fuel to keep the pump temp down, but to run out occasionally is not as bad as overfilling. The pump can handle getting warm, as said before overfilling causes the charcoal canister to become saturated with fuel which will lead to more expenses.

 

Wonderful. How would I tell if I screwed that canister thing up? I do fill up between 140-150 just in case. So maybe I'll fill up some gas cans this weekend and see how much fuel is really in it. I REALLY don't want to do that but... Maybe that, then drop the tank and try that. Everything I've read about the tank sounds like a real PITA... True? Can't thank y'all enough for helping with this.

 

Here is how to check the "harness" end of the fuel sending unit connection:


If you short pins 2 and 3 the fuel gauge should read "F" or more; also check the voltage between pin 2 and ground--it should be a nominal 5V (4 to 7 V is OK)--if either test does not met the specs the combination meter and/or wiring is bad.

Next test the sending unit resistance with the tank filled. The resistance between pins 2 and 3 should be 5 to 6 Ω--keep in mind the connector diagram above is shown facing the harness end, the sending unit end will be the opposite--if not the sending unit is bad:

 

Could just be a bad ground...therefore you get a bad reading...hope that wasn't too dramatic.

 

Cliffyk can't thank you enough for breaking that down for me!! FYKPUNK I appreciate the simple look first LOL thank you EVERYONE for all the help and ideas. I've had so many issues with this truck so it's just one more thing and I'm trying not to shell out big bucks if I can avoid it. So truly thanks to all!!!

 

One last question guys - in y'all's opinion, easier to drop the tank or take the bed off to access everything?

 

I never pay any attention to the fuel gauge anyway, they could build trucks without them and I'd not mind. I already have a pretty good idea of how far I can drive on a tank anyway based on the fuel mileage. I reset the trip meter and use it to determine when to buy gas. For normal everyday driving I fill up at about 250 miles, interstate only I'd go 300 miles. I could probably go another 50 miles or so, but why take chances.

 

If you have the people to help take the bed off. way easier. plus you can clean the frame under it also