Stock XJ Cherokee Tech. All XJ Non-modified/stock questions go here XJ (84-01)
All OEM related XJ specific tech. Examples, no start, general maintenance or anything that's stock.

Changed manifolds, oil inside the intake runners

Old Feb 22, 2017 | 10:00 AM
  #1  
rklettke's Avatar
Thread Starter
Senior Member
 
Joined: Oct 2011
Posts: 542
Likes: 2
From: Phoenix, AZ
Year: 1998
Model: Cherokee
Engine: 4.0 L6
Default Changed manifolds, oil inside the intake runners

I've got a 98 XJ with the 4.0 and aw4.

I upgraded to banks torque tubes and the 99+ intake (haven't started it yet because I need to figure out vacuum lines...) Anyways, there seems to be a lot of oil inside the old intake and on the intake ports on the head. At first I was thinking blow by but I don't have any oil inside the air filter anywhere I can see. Could the oil have seeped past my manifold gasket? (my valve cover leaks...)

Also I replaced the two elbows on top of the valve cover a few months ago. Pcv valves? One is just clean through I think. Or maybe they both were...
Reply
Old Feb 22, 2017 | 11:00 AM
  #2  
rklettke's Avatar
Thread Starter
Senior Member
 
Joined: Oct 2011
Posts: 542
Likes: 2
From: Phoenix, AZ
Year: 1998
Model: Cherokee
Engine: 4.0 L6
Default

Also, if anyone could give me the bolt size for the iac... I lost one of them and I can't get it off without removing the TB.
Reply
Old Feb 22, 2017 | 12:54 PM
  #3  
Alex V.'s Avatar
Newbie
 
Joined: Feb 2017
Posts: 19
Likes: 0
Model: Cherokee
Default

Severe blow-by can cause positive pressure in the valve cover and PCV system, but I'd first make sure your PCV valve and hoses are connected and working right. At idle there should be zero pressure or slight vacuum at the oil fill cap - if that isn't all right it could allow oil droplets/vapor into the intake. If oil from the leaky valve cover was getting inside the intake that'd mean you have a doozy of a vacuum leak and corresponding performance issues.
Reply
Old Feb 22, 2017 | 05:35 PM
  #4  
rklettke's Avatar
Thread Starter
Senior Member
 
Joined: Oct 2011
Posts: 542
Likes: 2
From: Phoenix, AZ
Year: 1998
Model: Cherokee
Engine: 4.0 L6
Default

I'll have to check that stuff. Do our xjs have an actual pcv?
Reply
Old Feb 23, 2017 | 07:44 AM
  #5  
cruiser54's Avatar
::CF Moderator::
 
Joined: Aug 2011
Posts: 43,971
Likes: 1,579
From: Prescott, Az
Year: 1990
Model: Cherokee (XJ)
Engine: 4.0
Default

It's very normal to see some caked on black crap in the intake runners.....
Reply
Old Feb 23, 2017 | 08:11 AM
  #6  
shooptube's Avatar
Senior Member
 
Joined: Feb 2014
Posts: 793
Likes: 5
From: Southgate, Michigan
Year: 1997
Model: Cherokee
Engine: 4.6 I6
Default

Originally Posted by cruiser54
It's very normal to see some caked on black crap in the intake runners.....
Cruiser is right. This was what mine looked like when I pulled the intake.

Changed manifolds, oil inside the intake runners-forumrunner_20170223_091121.png
Reply
Old Feb 23, 2017 | 08:41 AM
  #7  
rklettke's Avatar
Thread Starter
Senior Member
 
Joined: Oct 2011
Posts: 542
Likes: 2
From: Phoenix, AZ
Year: 1998
Model: Cherokee
Engine: 4.0 L6
Default

Originally Posted by shooptube

Cruiser is right. This was what mine looked like when I pulled the intake.
Yep that's just how mine looked.
Reply
Old Feb 23, 2017 | 01:12 PM
  #8  
salad's Avatar
Herp Derp Jerp
Premium Member
 
Joined: Nov 2011
Posts: 18,251
Likes: 17
From: Parham, ON
Year: 1999
Model: Cherokee
Engine: 4.0L OBD-II
Default

The CCV's job is to suck oil vapours out of the engine and into the intake. Totally normal. Older vehicles just barfed that stuff onto the road.

If you want nasty, look at a diesel with EGR and CCV from 1999-2006. The soot mixes with oil and creates a lot of hard gunk.

Clean it up and carry on!
Reply

Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 

Thread Tools
Search this Thread

All times are GMT -5. The time now is 01:17 PM.