So ive noticed the smell of gas vapor in the car. People generally attribute that to the gas tank prone to cracking. But i was parked in a garage over the weekend...smelled the vapor outside the car and followed it to the gas cap. I could hear it hissing. Clearly, this is my problem.

I faced this once before on my S10 after I REMOVED the whole evap system because the charcoal canister was in the way of my axle when i lowered it. Does anyone know the workings of the evap system on these cars? Where should i start looking for a problem? Probably a dead purge valve im guessing.