PCV??

rondo

New member
1052821

O.K. here's what might seem like a stupid concern, but I am a little confused. Got a '99 Sport, 4.0 I6 and I wanted to do some routine maintenance on it. Stopped at a local auto parts for a PCV valve, and after looking in his books, the guy says he can't find one so could I go pull mine and get the numbers from it?

Well I go out to pull it and he ends up coming out in about 2 minutes. He proceeds to tell me that there is no PCV valve for this engine (model). Well I'm pullin' on what looks like a PCV valve to me (top front on the valve cover with a direct line to the airbox), so I says "What's this then?" He says that it's just a breather and it's not the same thing. Sure does look like a PCV valve to me, but am I wrong here, or what's the deal? I mean; isn't a PCV valve sort of a breather anyway?

Geez, I feel like an idiot askin' this!

:-? [addsig]
 

1052822

that's no idiot question. i stumbled across the same thing. until i actually pulled my valve cover off, i had no clue how the system worked. if you're standing in front of your engine, at the back of the valve cover, there's a little grommet with a tube heading out of it that leads to your intake manifold somewhere. that hose is your PCV system. the valve is NOT located in the valve cover. you'll probably also need to clean that hose out being as it is very thin... here's what i did to clean mine:
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i used engine degreaser, sprayed it down the tube, then followed it up with 120 psi from the bicycle pump. it finally gave through and now it actually lets things through! :) lol
[addsig]
 
1052831

I suppose that worked but you can also take the easy and cheap route. The Dodge/Jeep dealer sells the tube/grommet/valve for about $15 and it is easy to change. :) [addsig]
 
1052899

On many Jeeps, the vacumn harness, comes as a set and is closer to $60-80 dollars. If they have it, in stock and/or if you can get them to order it for you (they usually like to keep that stuff for there own mechanics) and if the right piece comes and if it fits.
Well anyway, Crankcase ventilation: the scavenger system, usually runs to the air cleaner somewhere, is is the main system for keeping the crankcase in a slight vacumn. When the throttle is closed (or the gas pedal released) the intake vacumn goes up, the air filter vacumn down, so there is usually an alternate system for ventilating the crankcase PCV, whatever it is, a valve (works only at high vacumn), a 2.3 mm vacumn line or whatever. One half of the system with the throttle open and the other half with the throttle closed. I guess they are both positive crankcase ventilation and both get gummed up alot (especially with cheap oil). ;-) [addsig]
 

1053158

Definatly not a stupid question. The item you are refering to a pcv valve is actually called a ccv valve for the jeep 4.0's The ccv valve is a dealer only item and for both halves will cost you between 50 and 70 bucks. You should try some bone yards and save some serious money. without the ccv valve the vehicle will not even come close to passing emissions testing, the ccv goes from the valve cover to a vacuum harness that combines all your vacuum lines with the air cleaner. Good luck.......Bullet[addsig]
 
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