I recently acquired a 2004 ION 2.2L that had been sitting in carport for 6 years. I changed all the old fluids, spark plugs and coil pak, alternator, serpentine belt, then drained the old gummy fuel from tank, dropped the tank and installed a new fuel pump and fuel filter. After thoroughly cleaning the tank and reinstalling it, I then began filling the tank with funnel and full 5 gallon gas can. I began pouring slowly and was surprised by the fuel backing up in the fill neck and spilling down the side of the car. I inserted a long flexible tube down into the fill neck and to the bottom into tank, without any blockage. Gas erupted from the tubing. So I let it rest for a little bit and tried to put gas in it again.... same results. Any suggestions as to why this might be happening? I was so bummed because after the $, the time, the labor, I was hoping it would start. Thanks.

 

I'm not at all familiar with an Ion, but it sounds like maybe there's a blocked vent or clogged vent tube somewhere. Are you sure you got all of the hoses connected when you put the tank back in? IDK, just guessing.

 

Sounds like a evap vent valve is stuck closed. There must be somewhere for the air to be displaced in order to make room for the gasoline that you are adding. That vent should be open to allow vapors from the gas tank to flow to the evap canister. If it sticks closed, there is nowhere for the air to go other than back up the filler pipe.

Don't know where it's located on an ion, but others do.

 

I'm attaching a diagram of the lines attached to the vapor canister located behind the fuel tank in the space between the tank and the spare tire. Make sure all lines are attached to the canister correctly. The vent lines from the filler neck and the rollover valve provide a path to the vapor canister during fueling. If these are misrouted or blocked, you will experience the symptoms you describe.


Saturn Ion fuel vapor lines

 

Thanks so much everyone. will not be able to try your suggestions until next week. Will keep you posted.