Can't fill the tank

I have a 2004 Nissan Sentra. When I tried to fill the tank the last couple times the pump would shut off like it does when you are full. I basically would have to sit there for 20 minutes to fill the tank (not sure if that would even work). Does anyone know what I can do to fix this myself, or is this something I need to leave to a professional?

If you have had the habit of topping off your tank(putting more fuel in after the pump shuts off the first time), you could have damaged your evap system

Topping off the tank (which is likely forbidden in your owner’s manual) can cause that problem. It also can be caused by a damaged hose etc. Some people report problems with one station but not another.

It was two different stations. Big bucks to get this fixed?

Use a small, flexible limb (branch), 1/2 inch thick by about three feet long. Put this into the filler tube and push down to resit the anti-spill valve in the base of the filler tube. If that doesn’t fix it, the filler vent tube may be damaged. Then, the filler tube, and or the vent tube, may need to be replaced.

Big bucks if it’s the charcoal cannister fouled by overfilling.

What’s with the EVAP system? The EVAP system isn’t even operational without the engine running! So,it’s NOT the EVAP system.

The filler hose/tube assembly may be the problem.

In order to get gas in the tank, the tank must vent the air at the same time. This is done by using two tubes. In one system, a seperate tube comes out the gas tank and attaches to the top of the filler neck. In the other system, there’s two tubes, one inside the other. The inside tube is the fill tube, and this attaches to where the gas nozzle is inserted and points down into the tank. The outside tube is the vent tube. This is securely attached to both the gas tank and the filler neck. If the inside tube is made from plastic, they’ve been known to break off and fall down into the gas tank. When this happens, the gas is now introduced into the gas tank down the vent tube. And the air can’t escape from the tank as it’s being filled.

Tester

Hellokit has it right. FORGET the evap system, that’s not it. There is an anti-rollover check valve (just a cork or plastic ball) in a cage in the filler pipe. Yours is stuck in the top of the cage, blocking fuel flow. Slide something flexible down the filler pipe to dislodge it. A length of fairly stiff 3/8 plastic hose works pretty good…Or a one piece whip antenna, something like that. Coat hangers SOMETIMES work but they are a little TOO stiff…

Worst case, locate the valve and remove it…

I had meant the charcoal canister, but used evap system instead.