Oil & the airbox?
- Thread starter J-Daddy
- Start date
Joopin
Super Moderator
It's the "Pcv valve"... only it's not. Instead a of a PVC valve, jeep used a vacuum system. Sometimes that vacuum line gets clogged up causing oil to be sucked up into the airbox. On the right side of the intake tube there is a small 1/8" hose coming off and going toward the firewall in a kinda Z shape. Take that off, blow some compressed air through it onto a rag (so you can see when the oil stops coming out), clean out the box, and you should be good to go.
Joop
Joop
Bounty__Hunter
Super Moderator
It's a CCV system (Closed Crankcase Ventilation). There is a large line from the airbox to the valve cover, this line is supposed to suck air from the airbox to allow filtered air into the crankcase. Crankcase vapors are then sucked from the valve cover through a vacuum line into the intake manifold to be burned.
95% of the time this vacuum line, or it's small inline orifice, becomes clogged with carbon. With no vacuum to the crankcase from the intake, the crankcase vapors (and accompanying oil) are sucked into the airbox.
Moral of the story, ensure the CCV system is working correctly.
95% of the time this vacuum line, or it's small inline orifice, becomes clogged with carbon. With no vacuum to the crankcase from the intake, the crankcase vapors (and accompanying oil) are sucked into the airbox.
Moral of the story, ensure the CCV system is working correctly.
J-Daddy
New member
Well we looked into it and I think we got his fixed, maybe....
But I got to looking and my XJ Cherokee is doing the same thing...I put a new air filter in it last week and I checked it yesterday and it's full of oil. And after driving it today it puked a nice puddle of oil in the driveway and it all came through the airbox. I took the lines off to clean them and got that taken care of but I also noticed a larger line coming off of the airbox lid that runs to a valve on the left inner fender was rotten and was collapsed so I had to rip it in half to get it off..I'm gonna pick up a new hose in the morning to fix that and see if that takes care of the oil in my XJ box problem....
Now if I can get my radiator overflow tank to stop leaking out the bottom I might be ok for a day or two. Time to replace some coolant hoses I guess.
But I got to looking and my XJ Cherokee is doing the same thing...I put a new air filter in it last week and I checked it yesterday and it's full of oil. And after driving it today it puked a nice puddle of oil in the driveway and it all came through the airbox. I took the lines off to clean them and got that taken care of but I also noticed a larger line coming off of the airbox lid that runs to a valve on the left inner fender was rotten and was collapsed so I had to rip it in half to get it off..I'm gonna pick up a new hose in the morning to fix that and see if that takes care of the oil in my XJ box problem....
Now if I can get my radiator overflow tank to stop leaking out the bottom I might be ok for a day or two. Time to replace some coolant hoses I guess.
