Welcome to Just Commodores, a site specifically designed for all people who share the same passion as yourself.

New Posts Contact us

Just Commodores Forum Community

It takes just a moment to join our fantastic community

Register

Vacuum Leak - Where should i connect this hose?

b0red2tears

New Member
Joined
Jan 29, 2018
Messages
5
Reaction score
0
Points
1
Age
37
Location
qld
Members Ride
vz ss 5.7
Hi,
I bought my car with several existing modifications including the over the radiator intake / k&N filter. I've noticed this open breather hose on the LH valve cover. It has a vacuum that builds the longer you hold your finger over it. I would have assumed the opposite - just blow by gasses and I can't see the cover connected to the intake anywhere... Logic would suggest this hose would normally connect to the intake or throttle body somewhere but there is no where obvious. Should I drill hole into the alloy air filter housing and add a fitting to connect it into there? Ive been browsing other posts that seem to mostly relate to installing oil catch cans but haven't seen anything that looks quite like this setup, possibly because i have the "fly by wire" electronic throttle?? Any suggestions would be very much appreciated, a vacuum leak like that can't be good
Car is 2005 VZ SS 5.7L LS1

https://imgur.com/a/zZ4G4Vv
[/IMG]
 

immortality

Can't live without smoky bacon!
Staff member
Joined
Apr 15, 2006
Messages
15,678
Reaction score
3,804
Points
113
Location
Sth Auck, NZ
Members Ride
HSV VS Senator, VX s2 Calais S/C
That's part of the PCV system if I'm not mistaken.
 

someguy360

Well-Known Member
Joined
Jan 29, 2011
Messages
2,344
Reaction score
543
Points
113
Location
Adelaide Hills
Members Ride
94' VR 304 - 05' Navara - 12' Sorento
As above, it's part of the PCV.

Off memory I think it goes to the throttle body or somewhere close.
 

Brandoz

New Member
Joined
Sep 3, 2018
Messages
2
Reaction score
0
Points
1
Age
24
Location
Queensland, Australia
Members Ride
VZ SSZ Ute
Hi,
I bought my car with several existing modifications including the over the radiator intake / k&N filter. I've noticed this open breather hose on the LH valve cover. It has a vacuum that builds the longer you hold your finger over it. I would have assumed the opposite - just blow by gasses and I can't see the cover connected to the intake anywhere... Logic would suggest this hose would normally connect to the intake or throttle body somewhere but there is no where obvious. Should I drill hole into the alloy air filter housing and add a fitting to connect it into there? Ive been browsing other posts that seem to mostly relate to installing oil catch cans but haven't seen anything that looks quite like this setup, possibly because i have the "fly by wire" electronic throttle?? Any suggestions would be very much appreciated, a vacuum leak like that can't be good
Car is 2005 VZ SS 5.7L LS1

https://imgur.com/a/zZ4G4Vv
[/IMG]
Hey there mate, that line for me, connects straight into the OTR as there should be rubber grommet for hose - run from that vacuum line.
 

b0red2tears

New Member
Joined
Jan 29, 2018
Messages
5
Reaction score
0
Points
1
Age
37
Location
qld
Members Ride
vz ss 5.7
Thanks for the replies. Yes I also found similar pics as above during my search. Whilst i couldn't find any that exactly match my setup, clearly it does go back into intake. So I drilled a hole into the OTR and connected it there. Seams to have improved idle a little but I am concerned that the dyno tuning was done with the leak present. Also it has been open a long time, would it be worth taking valve cover off, is there anywhere dirt and crap may have been caught up?
 

greenacc

Searching for the billion
Joined
Jul 13, 2008
Messages
5,679
Reaction score
1,148
Points
113
Location
Sydney
Members Ride
VE Berlina
I wouldn't bother pulling rocker cover off just to look for dust.
 
Top