poor mileage 2.2L

Started getting poor mileage last summer i've done a complete tune up and o2 sensor.Computor says it's running to specs. But today it started to sputter coming off the light and I think i smelled gas? CAN SOMEONE HELP ME?

them problems come with age of the car.If u feel froggie u can look around for a new engine

do you smell it when you turn the heat on, if so its a rubber o ring on the gas line right around the intake on the left side, i had that problem it reeked!!!!1

dude this happens alot with the sunfires. it took me a week to fix the problem. the fuel injectors have a small round rubber gasket on the bottom of them. they go bad.lol it will cause the car to smell like gas. usually through the air vents in the car or outside near the winsheild wipers. one more thing is it could be the throttle body gasket or if you will the manafold gasket. cheap if you can do it youre self

Check your fuel pressure regulator vacuum hose.
If the diaphragm inside the fuel pressure relator fails, it will allow to suck the fuel into the intake and causing it to run rich and extra fuels are not burned.