PCV Valve Problem - JeepForum.com
Reply
 
LinkBack Thread Tools
post #1 of 16 Old 01-02-2014, 01:17 PM Thread Starter
adamcarner
Registered User
2012 JK Wrangler 
 
Join Date: Jan 2014
Location: Clinton, CT
Posts: 24
PCV Valve Problem

Hey all,

New to the forum!

I have a classy 1990 Wrangler 4cyl. My PCV valve keeps popping off whilst I drive the beast. The engine runs fine and purrs like a kitten. But it seems like there is too much pressure under there? does that even make sense? How can I prevent that bad boy from popping off, and seeping burnt oil smoke into my cabin, PLEASE HELP!



adamcarner is offline  
Sponsored Links
Advertisement
 
post #2 of 16 Old 01-02-2014, 02:13 PM
Mark05059
Registered User
1989 YJ Wrangler 
 
Join Date: Mar 2009
Location: quechee Vermont
Posts: 4,687
remove the valve cover, under the valve cover is a plate that is attached to the underside that gets plugged with crud. Its like a baffle. Also check the elbow for being plugged up.

1998 ZJ 5.2 Auto

1989 Wrangler Black Bone Stock 2.5l 5spd
/l , [____],
|---L--[]lllllll[]-
()_) ()_)==O=)_)
Mark05059 is offline  
post #3 of 16 Old 01-02-2014, 05:22 PM Thread Starter
adamcarner
Registered User
2012 JK Wrangler 
 
Join Date: Jan 2014
Location: Clinton, CT
Posts: 24
Quote:
Originally Posted by Mark05059 View Post
remove the valve cover, under the valve cover is a plate that is attached to the underside that gets plugged with crud. Its like a baffle. Also check the elbow for being plugged up.
Forgive my ignorance, but "the elbow?" Still new to the jeep world, my friend!

"The best kind of person is the one that comes into your life, and makes you see sun where you once saw clouds." KCCO!
adamcarner is offline  
post #4 of 16 Old 01-02-2014, 06:10 PM
90DesertTanYJ
Registered User
1990 YJ Wrangler 
 
Join Date: Jun 2012
Location: Jacksonville
Posts: 749
There should be another port with an elbow in your valve cover that leads to your air cleaner assembly somewhere. This provides filtered air into the engine while the PCV has a vacuum pulled from your intake. Not entirely sure where on the 4 cyl. FI motors. I have a carbed 6 cylinder but the principles are the same. Look closely at your valve cover and there should be two hoses leading away, one is the PCV and one is the CCV. Make sure your PCV is operating by taking it out and shaking it. You should hear the ball inside moving around. The elbow has no ball or any other parts. Just make sure it is clear. The baffle below the PCV keeps oil from being sucked back into the intake but will accumulate crud enough to plug it off. Check tha as well. You might get another valve cover grommet for the PCV and that might help but you may have more serious issues causing pressure enough to pop the PCV out.
90DesertTanYJ is offline  
post #5 of 16 Old 01-02-2014, 06:25 PM
jaycal3
Registered User
1993 YJ Wrangler 
 
Join Date: Mar 2009
Posts: 1,266
Quote:
Originally Posted by adamcarner View Post
Forgive my ignorance, but "the elbow?" Still new to the jeep world, my friend!
The elbow is just the bend in the valve... its bent like an elbow. Often times the valve gums up and does not function properly. When it does this, the "ball" inside cannot move and the pressure builds up thereby blowing the valve off the valve cover.

BTW, what makes your Jeep a "classy" one??

93 YJ, 6 cyl,3.5" BDS,1" Prothane BL,1/2" booms, 33" Mickey Thompson MTZ on MT Beadlocks.

Do your part for Leukemia research - help find a cure.
http://mskcc.convio.net/goto/Jay_Calabrese
KCCO
jaycal3 is offline  
post #6 of 16 Old 01-02-2014, 07:13 PM Thread Starter
adamcarner
Registered User
2012 JK Wrangler 
 
Join Date: Jan 2014
Location: Clinton, CT
Posts: 24
Oh, I replaced the PCV Valve, it's brandy new! Is this elbow the black plastic bend thats attached to the top of the PCV and goes into the hose? If so, thats brand new.

Quote:
Originally Posted by jaycal3 View Post
BTW, what makes your Jeep a "classy" one??
And that was a bit of sarcasm, hah! It's a cranky, crotchety old jeep

"The best kind of person is the one that comes into your life, and makes you see sun where you once saw clouds." KCCO!
adamcarner is offline  
post #7 of 16 Old 01-02-2014, 07:31 PM Thread Starter
adamcarner
Registered User
2012 JK Wrangler 
 
Join Date: Jan 2014
Location: Clinton, CT
Posts: 24
SO this is not my engine, but it looks identical, and it's out of a 90 wrangler 2.5L like mine.



So, I'm not versed in jeep engines, so just for clarity, The YELLOW circle is the PCV Valve, which I replaced and is brand new + put in a new valve cover grommet for it too. The BLUE circle is one that I never fiddled with.

The YELLOW is what is popping out under pressure. Is there something I can do to the BLUE one? That seemed okay!

I just wanted to be as clear as possible, as I'm not familiar with terms! bare with me!

"The best kind of person is the one that comes into your life, and makes you see sun where you once saw clouds." KCCO!
adamcarner is offline  
post #8 of 16 Old 01-02-2014, 08:46 PM
jaycal3
Registered User
1993 YJ Wrangler 
 
Join Date: Mar 2009
Posts: 1,266
Quote:
Originally Posted by adamcarner
SO this is not my engine, but it looks identical, and it's out of a 90 wrangler 2.5L like mine. So, I'm not versed in jeep engines, so just for clarity, The YELLOW circle is the PCV Valve, which I replaced and is brand new + put in a new valve cover grommet for it too. The BLUE circle is one that I never fiddled with. The YELLOW is what is popping out under pressure. Is there something I can do to the BLUE one? That seemed okay! I just wanted to be as clear as possible, as I'm not familiar with terms! bare with me!
I would check the lines that go to/from the PVC for any clogging. You may also have to remove the valve cover and clean out the baffles as mentioned earlier although I am not sure your engine is set up with the same baffles as mine, which has a ccv (it's a straight 6, 4L). You've got some crazy pressure building up under that valve cover.

93 YJ, 6 cyl,3.5" BDS,1" Prothane BL,1/2" booms, 33" Mickey Thompson MTZ on MT Beadlocks.

Do your part for Leukemia research - help find a cure.
http://mskcc.convio.net/goto/Jay_Calabrese
KCCO
jaycal3 is offline  
post #9 of 16 Old 01-03-2014, 05:38 AM Thread Starter
adamcarner
Registered User
2012 JK Wrangler 
 
Join Date: Jan 2014
Location: Clinton, CT
Posts: 24
Quote:
Originally Posted by jaycal3 View Post
You've got some crazy pressure building up under that valve cover.
I know, It's crazy. It was totally fine last week, this just started happening without warning. I'll see what i can dig up. In the mean time, is there anything else I can check?

"The best kind of person is the one that comes into your life, and makes you see sun where you once saw clouds." KCCO!
adamcarner is offline  
post #10 of 16 Old 01-03-2014, 07:28 AM
Mark05059
Registered User
1989 YJ Wrangler 
 
Join Date: Mar 2009
Location: quechee Vermont
Posts: 4,687
you can do a compression check and see if your getting blowby and pressurizing your crankcase...

1998 ZJ 5.2 Auto

1989 Wrangler Black Bone Stock 2.5l 5spd
/l , [____],
|---L--[]lllllll[]-
()_) ()_)==O=)_)
Mark05059 is offline  
post #11 of 16 Old 01-03-2014, 09:43 AM
tchoberg
Registered User
1987 YJ Wrangler 
 
Join Date: Sep 2011
Location: Winchester
Posts: 105
Reread this posted by 90DesertTanYJ, especially the underlined part.

Quote:
There should be another port with an elbow in your valve cover that leads to your air cleaner assembly somewhere. This provides filtered air into the engine while the PCV has a vacuum pulled from your intake. Not entirely sure where on the 4 cyl. FI motors. I have a carbed 6 cylinder but the principles are the same. Look closely at your valve cover and there should be two hoses leading away, one is the PCV and one is the CCV. Make sure your PCV is operating by taking it out and shaking it. You should hear the ball inside moving around. The elbow has no ball or any other parts. Just make sure it is clear. The baffle below the PCV keeps oil from being sucked back into the intake but will accumulate crud enough to plug it off. Check tha as well. You might get another valve cover grommet for the PCV and that might help but you may have more serious issues causing pressure enough to pop the PCV out.
I believe your problem lies with your 'blue circled' device which lets the 'filtered air in' which may be plugged allowing pressure to build and pop out the PVC valve.

If it ain't broke, don't fix it - Don't worry, something will break soon enough for you to fix.
tchoberg is offline  
post #12 of 16 Old 01-03-2014, 07:04 PM Thread Starter
adamcarner
Registered User
2012 JK Wrangler 
 
Join Date: Jan 2014
Location: Clinton, CT
Posts: 24
Quote:
Originally Posted by tchoberg View Post
Reread this posted by 90DesertTanYJ, especially the underlined part.



I believe your problem lies with your 'blue circled' device which lets the 'filtered air in' which may be plugged allowing pressure to build and pop out the PVC valve.
Oh thanks man! I totally overlooked that post. Ill do a check on that once the snow clears a bit more here, (In New England) Perhaps tomorrow. Ill post what I find!

Thanks again for all the suggestions

"The best kind of person is the one that comes into your life, and makes you see sun where you once saw clouds." KCCO!
adamcarner is offline  
post #13 of 16 Old 01-17-2014, 12:14 AM
Landslide
Registered User
1990 YJ Wrangler 
 
Join Date: Jun 2008
Location: Empire,CA
Posts: 35
If all the grommets are correct and good, PCV valve is new and is still popping out you got some crazy blow-by, also check to see if oil is coming out of dipstick hole.
Landslide is offline  
post #14 of 16 Old 01-17-2014, 07:49 AM
Que89YJ
Web Wheeler
1989 YJ Wrangler 
 
Join Date: Apr 2008
Location: Detroit
Posts: 20,800
Check the hoses the pvc and vent tube run to. The hoses get plugged and cause the pressure to build. Check both hoses to make sure they are clear all the way through.
Que89YJ is online now  
post #15 of 16 Old 01-18-2014, 08:46 AM Thread Starter
adamcarner
Registered User
2012 JK Wrangler 
 
Join Date: Jan 2014
Location: Clinton, CT
Posts: 24
Hello again!

So, I honestly think something was maybe half gelled or even slightly frozen that day (Twas Cold) But I just took it for a test run, let 'er warm up and it didn't pop off!! She's purring fine with no oil leaks!

I'll update if anything else happens!

Thanks again for suggestions. I'll check those hoses anyway to clear out any gunk that may be there

"The best kind of person is the one that comes into your life, and makes you see sun where you once saw clouds." KCCO!
adamcarner is offline  
Reply

Tags
1990 , pcv , pcv valve , wrangler , YJ

Quick Reply
Message:
Options

Register Now



In order to be able to post messages on the JeepForum.com forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.

User Name:
Password
Please enter a password for your user account. Note that passwords are case-sensitive.

Password:


Confirm Password:
Email Address
Please enter a valid e-mail address for yourself.



Email Address:
OR

Log-in









Human Verification

In order to verify that you are a human and not a spam bot, please enter the answer into the following box below based on the instructions contained in the graphic.




Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools
Show Printable Version Show Printable Version
Email this Page Email this Page



Posting Rules  
You may post new threads
You may post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are On
Refbacks are On

 
For the best viewing experience please update your browser to Google Chrome