Searching4Sierra

iTrader: (27)

can i just put a vacuum cap on the pcv valve thats right next to the pass. side valve cover, so i can run an open air filter set-up instead of the stock box. or do i need to keep that plugged into my airbox? thanks

or could i put a breather on the end of the hose?

Texas Terminator

hell no! the crankcase builds a little pressure not to mention all kinds of toxic and corrosive byproducts that need to be vented/burned.

speed01rcr

I know this an old quote, but that line going from the passenger valve cover to the T.B. is a vent that sucks air into the valve cover. Its actually rammed in there from the T.B. it seems. THere is no oil residue anywhere at all on that hose like the PCV valve hose.

Since that is the case, plugging that line there, and installing an oil cap breather would be the same...wouldn't it?

Zick

iTrader: (18)

Actually no, it sucks from the valve cover into the intake. Do a search on "catch can" and you'll understand.
The intake manifold is under vacumn and the crankcase builds pressure. What do you think is going to happen.

speed01rcr

Actually sort of. And I answered my own question at the same time. It recirculates the crankcase, but putting a breather would allow unmetered air in the manifold causing a lean mixture. Leaving the tube on the R/H side plugged into the T.B. from the R/H valve cover would allow it to draw metered air.

smooth_addictions

im currious as to why yo need to get rid of the pcv valve? my roomate and i both have open elements and still have our pcv's.https://www.performancetrucks.net/fo...e=1&p=3240338#
Huh

speed01rcr

I'm not, but I think the first guy that started the thread was talking about the vent line. The PCV valves I know of are on the L/H side of the engine.

smooth_addictions

can you say c.a.i. you are right it is on the l/h and that is the ventline

02sierraz71_5.3

iTrader: (2)

the only reason for having the pcv valve and venting into the intake is for emmisions. Put a breather on the valve cover opening and plug the vacumm line that leads to the intake
The end no more oil consumption

BTW: there is no such thing as unmetered air if your running in SD

budhayes3

iTrader: (19)

The pcv system also helps to relieve crank case pressure which your seals and gaskets will like. Too much pressure in the crank case can lead to blown seals resulting in external leaks and/or oil blow-by into the combustion chambers/cylinders. I personally can't think of any good reason to remove the pcv system on a street driven vehicle, especially since the engineers who designed the engine control system have figured that "controlled vacuum leak" into the equation. On a full race vehicle, you can get away with breathers, maybe, but I wouldn't do it on a fuel injected street vehicle.