No its not from the intake hitting the chasis, I took care of that already. Its some knocing noice. First of all, I dont even know how to change the timing, and the only thing I did in the engine was remove the airbox, and put in the intake, I didn't remove or change around any sensors, so I couldn't have done anything wrong. Maybe it's because when the airbox was there, the sound was not as noticable, but it is a little bit more now. So I dont know whats wrong. (My dad's 91 Oldsmobile cutlass cierra knocks like crazy but still runs like new)