Valve Cover Hose To Intake

[TECHNICAL 5]

Hey if i disconnect the hose going from my valve cover to the intake tube will it cause problems.I disconnected it , put a breather filter on the little tube sticking out from the valve cover and plugged the hole on the intake tube. I did a search and found nothing. Must be a purpose for this hose i guess.

 

[derrick1623]

melanism has done this, and no problems yet...what did you "plug" the intake with?

 

[TECHNICAL 5]

I was thinking maybe the intake sucks air out or releases some sort of pressure thru this hose from the cams moving around under the valve cover.I dont know i was just wondering. BTW i plugged it with a rubber plug

 

[twizyours]

The hose to the valve cover you are talking about is just the breather. All cars have them basically you shouldnt have any problems might get more air but also might pull in hotter air to. Never heard anyone have problems buy doing that. For you info OBX makes a metal cased one with a washable foam insert. I had a red anodized one on my probe GT. Tey come in three colors red, blue, chrome.

 

[twizyours]

Buy the way on probes I found over time they start pushing oil threw that hose into the intake tube, so I usually change them on my cars. I am not sure yet if I am on this cara but probally. That is the F2 by the way.

 

[Equinox]

there was an article in sport compact car about those lame ass breather valves and the hose from intake to valve cover. The summary of what the said is the hose from intake to valve cover is better than a breather, a breather causes equal pressure with the engine bay and therefore doesn't do much of a job. With the intake and hose you create a low pressure area in the valve cover, creating a near perfect vaccum. THey said a breather compared to a hose would cause about 1/4 hp loss.

 

[twizyours]

That is interesting and on a new car I dont think it is worth changing. After reading this I went and got my OBX foam canister one that I had on my probe and there was oil in the canister . I was suprised to see it but I do know on probes that they push oil int the intake over time. I woul rather lose a half a horsepower then push oil in my intake. What is your opinion? Is there anyone withe the old FS engines do they push oil in the intake over time. I will see if I can get pics of the oil in the breather canister on the internet.

 

[saided18]

well maybe the other guys was rite BUT as i knwo it that hose is for emissions. this is b/c where the valves are there is created some kind of exhuast fro gtom the hot oil or some thing. But whats the hose does is lets that air in the valve area is sucked into the intake and then into the cylinders to be burnt. This is why in NJ you can't pass emission if you have one of those litte filters instead of the hose. hope that makes sense.

 

[twizyours]

I thought the air comes from the intake and the gas is post to go through the PCV valve and into the intake manifold. Correct me if I am wrong.

 

[Sir Nuke]

okay....here we go....the purpose of that line is to VENT the valve cover.....so that presure will NOT build up in there and possibly blow out your valve cover gasket.....if our engines were push rod engines (which they aren't we have over head cams) it would allow any presure built up in the crankcase to vent out.....its still possilbe to build presure in the valve cover if the valve guides/seals leak some....not to mention as things heat up and the cams are spinning around.

by removing the hose and putting a vent filter on there you will still have the ability to get any unwanted presure out of the valve cover and you will be fine....HOWEVER do not be surprised if the oil mist that is present in the valve cover starts to accumulate in the filter after a while and start to drip.....just something else to keep cleaned up.

 

[Traveler]

Okay, let me put this to rest once and for all. The hose attached to the valve cover is a crankcase breather. BUT it let's filtered air INTO the engine not out. The PCV valve uses vacuum to pull crankcase vapor into your engine to be burned, and the breather let's in more filtered air. When the PCV valve is 'closed' under high vacuum situations, it still let's some air in. The breather can also let high crankcase pressure out, but you shouldn't have high pressure in the crankcase unless you have a serious blow by problem.

Older engines had a small filter in the air filter housing that filtered air seperately from the intake air. These usually plugged up with oil when your engine had a few miles on it, or they got taken out. The reason the newer engines (last 15 years or so) have the breather hooked to the intake is because there is only the one filter to change and keeps dirt from being sucked into your engine through a dirty or missing breather filter. There is a oil seperator in your valve cover that keeps any engine oil from getting back into your intake tract also (ideally). If you ever start getting oil back into your intake it means one of three things. Your PCV is plugged, your rings are shot, or the oil seperator isn't allowing oil to drain back and is letting it back up into the intake.

 

[saided18]

well then why in my state (NJ) they will not let you pass for emissions if you have a filter and not a hose????

 

[promp3]

So if my top end is making pressure and venting it in to my intake that means I'm making boost! yay! .ooooo5 bar! yay! I need a bov now.