From what I remember when I replaced the gas tank in my old Grand Am (which is probably almost the same as your Grand Prix) it shouldn’t be too hard of a job.
is it throwing a check engine light? Take it some where and smoke check it for leaks. Filler neck is really the only logical answer from the info that you provided.
def, and I honestly I dont think its to cheap to replace… I know on a chrysler mini van that i did one on it was 400 for just the filler neck, but I wish u good luck I hope its alot cheaper for ya
I know a few people told you to take it to a shop and that you didn’t want to take anything apart also. I would at least run your car up on some ramps and give it a good look. From what I remember this should be a very simple job. Find a car buddy to give you a hand. Run the car out of gas and take the gas cap off to air it out. If it’s over your head then take it to a shop. I would at least take a look at it first.