Hello XXXXXXXXX and welcome to Just answer.com, Super mechanic here. About your Geo tracker.
There must be a problem with the 2 way check valve on the top of the gas tank. It is designed to stop raw fuel from entering into the vapor canister. If the tank has been removed and replaced then it is possible that it is in backwards.
In anycase, you will want to check it. Here is a picture of it.
That might be too small for you to see, here is a bigger one, (lol)
Master technician
29 yrs. exp., ASE master, cert. in G.M. electrical, a/c, susspension, brakes, electronic steering