[mengel]

Is this an LSI model? If so, I think this is the one you want (I'm trying to remember exactly.. this solenoid I describe below is the one that gives you the same code that a loose gas cap gives you):

...get on your back, and scuttle under the car at the rear. Look up at the gas tank, and move slightly towards the front of the gas tank. The valve/solenoid is mounted right on the underside of the body, right next to the evap canister that's under there, dead center of the front of the gas tank. It has a couple small hoses going to it, and the electrical connector. if you are careful, (and double-jointed, with small hands!) you can remove it without removing the whole canister it's mounted on like the manual tells you to. It's about $80 US. I've replaced a couple of them over the last few years on my '98 LSI model. This last time a few months ago, I made a metal shield, and screwed it over the solenoid as a cover, to keep it protected from all the road crap that destroys it.