When my rx8 idles, I can hear a distinct rapping, tapping sound under the plastic intake manifold. It seems to be in the area where the plastic manifold ties into the metal portion of the manifold. The tap is a regular tap-tap-tap-tap at about three or four hertz and in sync with the idle. It disappears as you climb out of idle. The problem hasn't increased after showing up and doesn't affect the idle at all. The sound can be heard inside the cabin.

I'm tempted to take the manifold off to inspect it, but I don't know if the sound is coming from the manifold itself for from a component beneath it and on top of the block.

Thoughts? Thanks

 

i will save you from the bashing of everyone saying search.

it is more likely than not your ssv making the noise

 

Sounds like a spark plug wire is loose. make sure theyre on tight