Ls6 Pcv and catch can setup causing knocking sound?
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Teching In
Joined: Oct 2025
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Ls6 Pcv and catch can setup causing knocking sound? My setup now is small end of pcv facing intake manifold and large end going into catch can, then catch can has a straight away tube into the crankcase.
Before I had it backwards basically having the pcv go into the crankcase and straight line from catch can into intake manifold, I also have my throttle body piped straight into the valve cover.
After i did the swap to the first paragraph stated i will experience a knocking noise only if i idle for too long wayyyy after being hot so basically at the end of the day when im just chilling with people, im curious if any of this has to do with any of the knocking or if its just a concidense, everything been fine after I cammed the car months ago until I actually tuned it right and also changed the o2 sensors so the car stops sputtering but now I get this knock after idling too long, but when I drive down the street it goes away intil I idle too long again, am I having an oil cavitation issue at idle? Maybe I need a new oil pump or atleast a higher output one maybe?
Before I had it backwards basically having the pcv go into the crankcase and straight line from catch can into intake manifold, I also have my throttle body piped straight into the valve cover.
After i did the swap to the first paragraph stated i will experience a knocking noise only if i idle for too long wayyyy after being hot so basically at the end of the day when im just chilling with people, im curious if any of this has to do with any of the knocking or if its just a concidense, everything been fine after I cammed the car months ago until I actually tuned it right and also changed the o2 sensors so the car stops sputtering but now I get this knock after idling too long, but when I drive down the street it goes away intil I idle too long again, am I having an oil cavitation issue at idle? Maybe I need a new oil pump or atleast a higher output one maybe?
