Check Engine Light/Limits Revs?

Hey guys, I'm not really familiar with the car scene or know much about engines or cars themselves. I came to you guys because no one else was able to help me. I have an '02 Gt-s with the check engine light on. We (Autozone, advanced auto, my father and I), have determined the problem happens at higher rpms when when the final pull of a gear happens between 7-7.6 rpms. I was told to clean the small bolt on part by the engine sensor but wasnt able to because some metal gasket has it stuck in there. I dont know how to remove the part. When I did clean a little of it, and the check engine light turned off. I floored it on the street only to find the light turning on again.. have you guys had this problem? My friend was who instructed me to clean it out.. I just need to know the permanent solution. If you guys could help out that would be great! And sorry for such a crappy exexplanation.. I'm sure you guys know what I'm talking about !