i have a 2007 h3 base 94k on it everything works great but i noticed a high pitch humming noise. i intsalled a k&n intake and thought it was that but its not. my h3 sounds like a rich burner right now the sound only comes when i am in drive or reverse. someone told me that it might be the transmission and changing the fluid might help the sound. when i baught the h3 4 months ago the sound was not there only after i isntaled the intake..any help is greatly appericated thank you in advance ..

 

sounds like you have an air leak somewhere, did you try putting the stock air intake back on to see if it goes away?

 

yes i put in back on and the sound is stll there. i thought it might be a ir leak but when the h3 is in park and i push the gas i dont here it only when in drive or reverese and there is no grinding noise just a high pitch noise when accerlating