So Im having to separate issues that i think are related. In ever gear at 3000rpm it feels as if im sputtering or bogging out and have kind of loss of power. it only happens at 3000RPM and goes away at like3500. Also when i open the gas cap a lot of air is released. Now i know that is somewhat normal but it pretty violent the amount of air coming out. i had about 3/4 of tank full and released the gas cap. it was so bad it actually spit out gas. I have a 98 SE 4cy. any ideas on what to look for would be great thanks all.