Air Bubble in Gas Tank?

Question

I have a 2005 Hyundai Elantra and just recently, when pumping gas, it shuts off, thinking it's full even though I'm on empty. A friend mentioned air bubble in tank. Can this be fixed and how?
Mahalo

Answer 1

Never in 40 years of in the business have I heard of an air bubble in the gas tank. I'd get it to a shop and have the filler neck and tube checked out. Could also be a problem with the pump.

Answer 2

Air Bubble In Gas Tank

Answer 3

You don't specify what year model the car is but assuming that it is newer than 96, the sound you hear is pressure if the tank is more than half full, and vacuum if it is almost empty. After 96 almost all cars have a system called the EVAP sys. Under the right conditions the computer will activate a pump which pressurizes the air space above the fuel in your tank then monitors a pressure sensor in the top of the tank and calculates the amount of pressure drop over a preprogrammed amount of time and uses this to determine weather the system is sealed properly or has a leak. when you remove the cap on a tank that is more than half full you are releasing this pressure. When you remove the cap on a tank that is almost empty you will release a vacuum that is caused by the fuel being pulled from the tank with no vent to replace the air meaning you have a good tight sealed system that is working properly(like sucking on a drinking straw that you put your finger on the other end of. the straw collapses due to vacuum.

Answer 4

Your gas filler tube has a vent tube that runs from the top of the filler neck to the tank.

This vent tube allows air to vent when you fill your tank with gas.

Your vent tube could have something blocking it or is pinched.

Have also see ,inside the fuel tank where the filler tube connects the tank.

Their is a round shaped disk that has a weak spring behind it.

So when you fill your tank the pressure of the fuel pushes it down 1/2 of an inch as you fill your tank.

The disk is their so people cant get a hose down in your tank to steal your gas.

Have the disk get stuck and not go down all the way causing your fuel to back up in your filler neck.

Have ran it to both over the years in our shop hope this helps.

Auto tec 14 years

Answer 5

Try pumping the fuel into the tank a bit slower.

Often times the displaced air in the tank will be forced out along with enough fuel to cause the auto shut off feature on the nozzle to cut off - this isn't an unusual problem.

Answer 6

This is caused by a bend or kink in the filler hose. That's the hose that goes from where you pump the gas down to the gas tank. I don't know why, but sometimes this can suddenly happen. You can pump the gas a lot slower and this might correct the problem'.



The other thing to do is crawl under the car and see if the hose is kinked. You might be able to loosen the clamps and twist the hose to align it.

Answer 7

If you have the nozzle in the neck of the tank wrong it can cause the gas to splash back and shut the pump off. Change the angle of the handle and fill it on slow. Will also save fuel to evaporation by runing the pump slow.

Answer 8

The gas tank is always full or air, Any volume that liquid fuel is not taking up. Always. So, I would buy gas at a different station and see what happens.



Some stations just pump gas way too fast.

Answer 9

Pump your gas slowly and never overfill it. If the evaporative emission system gets filled with liquid it will cause gas fumes to escape and can cause problems like you are experiencing.