Considering it's a Chevy, as I own a 94 Chevy Lumina, you may have the similar problem I had. My car smelled of gas, but would refuse to start. We found out through a garage that at first it was the Ignition Modulator Sensor then 5 months down the road the computer went, (but then we didn't smell gas). My Lumina left me stranded 5 times. We waited for a day, and it would run fine again. A couple of times my hubby though I was out of my mind, because it would start up for him, but not me. The last time it did it, was at a garage, because we thought it was a fuel pump, but the mechanics said I had plenty of fuel pressure. It went down, the mechanic hooked it up to the diagnostic tool, and lo and behold, it was the ignition modulator sensor. See if you can get it put on a diagnostic tool to help you figure it out and pin point the problem. Good luck and hope it works out.