K & N Filter on 496 HO Whistling Noise
 

Anybody know how to stop the whistling noise on 496 HO? It wont stop until 3400 rpm?

change out the IAC muffler in the TB..possible IAC needs to be replaced

possible the IAC muffler might have degraded and injected itself is another area to check out very closely. Not uncommon because not many do IAC system maintenance.

IAC hose connections

IAC muffler missing

IAC muffler completely dirty causing a huge restriction

Scan engine look at % of IAC pulse width modulation = IAC not functioning properly.

Throttle body really dirty and IAC passages

really dirty Flame Arrestor - when is the last time it was 100 % cleaned a huge IAC killer and noise