Kreeess

Okay... So lately I've been trying do diagnose the intermittent hesitation during a WOT or under load on my 98c5... I'm going through the steps in checkin if everything is ok with no leaks... While i was checking my PCV hoses I remembered I did the 01-03 ls6 valley pan which had an internal PVC system.. ( and so I thought!?) only the 04 had the internal and the older style ls6 valley pans STILL required and external valve... Since we added a catch can on the car the hose seemed a little tricky to me to figure out lol but I realized that there was NO PCV valve connected at all... Is this bad? Could this be the cause of my intermittent hesitation? What should I do if I wanted to add a PCV valve I only have regular vacum hoses ... I noticed the valves require the adaptor to connect to the vacuume lines...

Here's what it looks like ... Where can I get the hose or can I just make my own so that a Pcv valve can fit?

vettenuts

Have you checked the PCV valve from the valley cover age appropriate car. It might actually be the same as your stock unit, but you do need some level of retriction in the line.

Kreeess

PCV valley is off a 01 zo6... so external PCV valve is needed, my question is... can i make a home made PCV housing or do i need to buy the $99 housing from GM?

Kreeess

found this through LS1.com since i have the earlier ls6 valleycover can i do this mod for the Valve housing, since my stock housing got thrown away?

http://www.ls1.com/forums/f6/pcv-val...ication-80151/

Bill Curlee

Just for the knowledge of how your PCV system is supposed to be plumed, here are the service manual drawings:

LS6:





LS1

Kreeess

thanks for the diagram Bill, since i have the older style ls6 valley i need the PCV valve but i dont have the hose fitting for it, wondering if anyone had a DIY or if there were anyway to fit it with some hoses and cuplinks OR if its even needed

vettenuts

The upper diagram is the setup you need. Have you tried a WTB in the for sale section or fleabay? Quite a few have upgraded or put in new motors and you might be able to pick one up.

Kreeess

probably just going to make a homemade housing for the valve there are a few reads on LS1.com on it hopefully it works..

im curious tho, vacuum leak can affect car performance correct? how about lack of PCV valve? no?

Bill Curlee

Lack of air flow thru the crank case causes moisture and acids to contaminate the oil.

TOO MUCH air flow causes migration of oil into the intake manifold. It also can cause idle and LTFT issues.

Your PCM is tuned to compensate for the induction of air around the throttle blade via the PCV system. If you remove the DESIGNED RESTRICTION of the PCV valve (vacuum metering device) the throttle blade will pretty much be fully shut at idle and that can cause idle RPM issues.

Kreeess

Thanks for the info bill!