For some reason my check engine light turns on intermitently when my car is going between 35-40 miles per hour, but today i noticed that it also does it when the engine is reving between 1000 and 2500 when the light comes on i also hear a loud buzzing sound coming through the speakers. does any one have aclue? Has anyone ever had this problem? I'm thinking of taking it to the stealership to see if it comes up with any diags but wanted to get some input here first. thanks for any help.