Things I would check:
-o2 sensor
-maf
-clogged catalytic converter (it made my stutter worse and smell of gas)
for the smell of gas, is it up front or in the rear, or at the tail pipe?
If its up front there are some fuel line hoses that have little screw clamps, check those and tighten them if need be. If it's in the rear, there is a seal on the top of the gas tank that leaks, even if you can see fuel dripping, it seeps out. If it's at the tailpipe, then you know its something with how its running, and not leaking.