For the last couple days my mr2 turbo has been making a horrible noise around 1600-1800rpms then goes away under or over that! It sounds like its coming from the head but i could be mistakin. At first i thought it was just a turbo gasket or somethin got loose but i don't see anything shaking up top at all! The car doesn't seem to drive any different but around those rpms the car sounds like complete shit!!!! anybody have any idea what it could be? please respond. i need all the help i can get!