2004 grand am Gas light stays on - 2004 Pontiac Grand Am

Good guess. I agree.

First check to make sure gas cap is on tight. (yes I know, sounds stupid but it's a possibility) If that doesn't cure light, stop into any good parts store like autozone, Advance, etc and have them do a FREE fault scan, they run the scan give you a print out and reset your lights. If light comes back on you HAVE an issue.

check the solenoids...
if you press on the gas and it stay on...then it should be one of the solenoids...maybe the idle solenoid

Check out this recall:

http://www.automotive.com/2004/49/pontiac/grand-prix/recalls/45415.html

Springs or the cable might be a problem. Check on the recall and then go from there.

What code are getting after all those new parts?
and what engine do you have,do you know what the original code was,because one code can do a domino affect to other sensors,it doesn't make them all bad.
your problems could be a lot of things ,faulty crank and cam sensors,egr valve leaking vacume,or intake leak of vacume.playing hit or miss with parts is really expensive.

Have these two things checked,
The idle air control valve
and the fuel bypass valve

the fan is a clutch fan.get it checked.
without hearing the noise it is hard to see

I had a check engine light on for my gas cap. I fueled up and sometimes it would say "check gas cap" So i just plugged it in under the steering wheel and cleared the check engine light from my dash board. So far so good.

Check all of your vacuum lines and their fittings.

crank shaft sensor or cam sensor