Hiss from intake with A/C on

[MOSHO92]

I have a conical K&N filter and there is a noticeable hiss from the drivers side of the engine when the A/C compressor kicks on. Iv'e notoiced this for four years now but just now got bored enough to ask.... What is it?

 

[AutoSHO]

Same thing as the hiss when you start your car in the morning cold- the IAB opening to maintain a steady idle.

 

[MOSHO92]

good to know. thanks for clearing that up. thumb