PCV modded to CCV
CF Veteran
Joined: Aug 2011
Posts: 10,489
Likes: 24
From: Nor-Cal Coast
Year: 90,84
Model: Cherokee
Engine: 4.0,2.5
It's actually a little motor. The computer moves the "pintle" in or out to do what we use to do with a screwdriver with the idle speed screw.
Don't power one up with it out! (might ruin it)
Last edited by DFlintstone; Mar 25, 2015 at 07:39 PM.
Junior Member
Joined: Mar 2015
Posts: 53
Likes: 0
From: Ludowici GA
Year: 1995
Model: Cherokee
Engine: 4.0
thats why i installed this. perfect fit. its free flowing like the original, except it has some of the foam inside to catch any oil that goes through it if the rear CCV gets clogged again
http://www.oreillyauto.com/site/c/de...0572&ppt=C0088
http://www.oreillyauto.com/site/c/de...0572&ppt=C0088
CF Veteran
Joined: Aug 2011
Posts: 10,489
Likes: 24
From: Nor-Cal Coast
Year: 90,84
Model: Cherokee
Engine: 4.0,2.5
I don't think the foam is a good idea. Good chance after it clogs up crankcase pressure will make oil leak places like the rear main seal. The CCV orifice can't keep up with any real blow-by you might have, say climbing a hill.
CF Veteran
Joined: Jan 2015
Posts: 2,152
Likes: 7
From: Minnesota
Year: 1999
Model: Cherokee
Engine: 4.0L
Senior Member
Joined: Nov 2009
Posts: 664
Likes: 49
From: napoleon ohio
Year: 98, 00, 01 and another 01
Model: Cherokee
Engine: both 01 jeeps have viper coil pack
The front one is harder to find. It is easier to go to O'Reily auto parts to the help section. There get a Dorman 47057 and make the hole bigger.
Senior Member




Joined: Nov 2013
Posts: 737
Likes: 31
From: Alaska
Year: 1999
Model: Cherokee
Engine: 4.0L I-6
My bad 
I went out and compared the front one on my '95 to the one on my '99 and they are different. It's not so much how they work, but how they fit. The one on the '95 is offset on the valve cover, and back between the throttle cables, and is as tall as the rear one. The front one on the '99 is centered on the valve cover, and way up near the front. It appears to be a lower profile one, I'm guessing for hood clearance. I don't know for sure, but I suspect the one on the 2001 is similar, and if the more common taller style were used, it may get smashed when the hood is closed.

I went out and compared the front one on my '95 to the one on my '99 and they are different. It's not so much how they work, but how they fit. The one on the '95 is offset on the valve cover, and back between the throttle cables, and is as tall as the rear one. The front one on the '99 is centered on the valve cover, and way up near the front. It appears to be a lower profile one, I'm guessing for hood clearance. I don't know for sure, but I suspect the one on the 2001 is similar, and if the more common taller style were used, it may get smashed when the hood is closed.
I think that in the ideal world with a good engine, The front draws filtered air in from the airbox and the rear is 'metered' with a smaller hole to draw out/vent and into the intake system under vacuum.
Over time with the rear getting clogged or with greater blowby, the front will act as the vent and oil will go into the air box. Oil in the airbox really means something is wrong.
A small filter on the front is the same as a tube plumbed into the stock airbox.
Over time with the rear getting clogged or with greater blowby, the front will act as the vent and oil will go into the air box. Oil in the airbox really means something is wrong.
A small filter on the front is the same as a tube plumbed into the stock airbox.
Herp Derp Jerp

Joined: Nov 2011
Posts: 18,251
Likes: 17
From: Parham, ON
Year: 1999
Model: Cherokee
Engine: 4.0L OBD-II
My bad 
I went out and compared the front one on my '95 to the one on my '99 and they are different. It's not so much how they work, but how they fit. The one on the '95 is offset on the valve cover, and back between the throttle cables, and is as tall as the rear one. The front one on the '99 is centered on the valve cover, and way up near the front. It appears to be a lower profile one, I'm guessing for hood clearance. I don't know for sure, but I suspect the one on the 2001 is similar, and if the more common taller style were used, it may get smashed when the hood is closed.

I went out and compared the front one on my '95 to the one on my '99 and they are different. It's not so much how they work, but how they fit. The one on the '95 is offset on the valve cover, and back between the throttle cables, and is as tall as the rear one. The front one on the '99 is centered on the valve cover, and way up near the front. It appears to be a lower profile one, I'm guessing for hood clearance. I don't know for sure, but I suspect the one on the 2001 is similar, and if the more common taller style were used, it may get smashed when the hood is closed.
In theory yes. In practice, the little breather filter needs to be at least the same efficiency as the OE air filter or you wind up sucking up dust. I don't think many of those breather elements are.
CF Veteran
Joined: Jan 2015
Posts: 1,381
Likes: 3
From: Southern Maryland
Year: 1991
Model: Cherokee
Engine: 1999 4.0L
Yeah its a concern. Generally you want it to be on main intake filter. Stock setups have it right at the filter, but the CAI setups usually have it on the tube (you can see the brass plug on my tube). The vacuum in the tube can get really high in some cases and I suspect it is starving the CCV inlet, and am testing a couple of alternative setups.


