vn commodore sucking noise

[commodore1994]

hi my vn makes a sucking noise from the air box. its pretty loud and only started happening after i replaced the throttle body

 

[tris909]

Most likely IAC valve not set correctly, to reset hold vehicle revs above 2500rpm in park/natural for more than 10 seconds to reset IAC position. once throttle is released it should idle down slowly to its steady state. let us know how it goes.

 

[VPRob]

Or one of the connections in the line from air filter to the TB isn't correctly seated and is sucking air

 

[delcowizzid]

its just the sound of air going through the IAC passage its different sounding due to how far open the throttle blade is compared to the old TB

 

[hi_ryder]

or its a v6 and makes sucking noises cause it sucks...

 

[somefool]

haha the v8 makes a way louder sucking noise compared the v6. and it does that 'old man sigh' when you turn it off. Or the v6 is the same but the rattles are louder than the induction noise who knows.

Just IAC it should reset after a little while. or as said

its just the sound of air going through the IAC passage its different sounding due to how far open the throttle blade is compared to the old TB

 

[Circlotron]

haha the v8 makes a way louder sucking noise compared the v6. and it does that 'old man sigh' when you turn it off.

That "old man sigh" when you turn it off. My old dirtbox makes a noise like that! Even when it's running sometimes. Sounds more like a whistling kettle boiling very slightly. If you block off the pcv air inlet to the drivers side rocker cover it gets way worse. Pretty sure it's actually the valley cover gasket not sealing properly across the front, right near the two temperature sensors. Danged pesky place to get to. Getting an endoscope camera to have a peek under there and hopefuly a bit of silastic will fix it. Kinda my own stupid fault - I partially blocked off the airbox inlet and gave it a big rev. LOTS of vacuum went from the airbox down the hose that normally supplies air to the pcv, not draws it out, and this vacuum found the weakest point. Coulda been a lot worse I suppose.