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Question about adding 2nd PCV. Please help.

  • Thread starter Thread starter daddystang
  • Start date Start date Aug 8, 2007

daddystang

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Aug 13, 2006
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Aug 8, 2007
#1
  • Aug 8, 2007
  • #1
I've posted a couple threads about my son and I adding a second PCV to the system. Some how the PCV valves are sucking up oil, because when I start it up it smokes a lot out of the tailpipes. We installed a home made baffle under the PCV valve we just added to the valve cover (I wish I had taken a pic of the inside of the valve cover).

I just started it after it sat for about 2 hours, and a lot of smoke came out the back. Did I do something wrong? Is there a difference between PCV valves? I don't know if I made a mistake, but I didn't buy the one the book at AutoZone said was for a 92 mustang. That one seemed too tall for the area where I installed it, so I got one that was the right size.

If anyone out there know where I went wrong, please chime in.

Thanks in advance.

Joe
 

vristang

15 Year Member
Mar 31, 2005
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Aug 8, 2007
#2
  • Aug 8, 2007
  • #2
It may not be the pcv that is contaminating the intake.

To confirm you can pull the pcv hose, and check for moist oil.
If I remember right though, your pcv/manifold inlet sits pretty low, so oil could be draining from the intake down the pcv hoses...
Just thinking out loud there...

Valve seals can crap out which would result in massive amounts of oil in the intake.


Maybe sticking a Home Depot separator on the pcv hose (just before the intake) will help confirm if oil is entering via the pcv.

Also, it may be worth while to check for engine vac in the crankcase...
Take a vac gauge and hook it up to one of the pcv valves. Then plug the other pcv valve. This *should* islolate the crankcase from intake vac.
If all is well, the vac gauge will read a little pressure.
If you get a vac signal from the crankcase, then most likely one of the intake/head gaskets slipped during installation.
Sometimes looking at the gaskets as they sit between the head and intake will hint to this as well, but it can be hard to see there...


that's about all I can think of right now.
jason
 

montegoman351

Member
Jan 12, 2007
169
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18
Aug 8, 2007
#3
  • Aug 8, 2007
  • #3
Ok, crazy question, Why do you have 2 PCV valves?
 

daddystang

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Aug 13, 2006
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Aug 8, 2007
#4
  • Aug 8, 2007
  • #4
Thanks Jason... Hopefully the valve seals are ok as the AFR heads have only been on for 1 year.
I'm going to let it sit tonight, and then start it up tomorrow morning and see if it smokes. I'm hoping it was just oil left over from running it with no baffle. When I was installing the baffle, I flipped the upper intake over and back, and some oil actually came out of it.

One thing though. Is it ok if the PCV valve I'm using isn't the one the book says is for the car? Are all PCV valves the same, just different shapes and sizes?

Thanks again.....

Joe
 

daddystang

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Aug 13, 2006
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Aug 8, 2007
#5
  • Aug 8, 2007
  • #5
daddystang said:
Thanks Jason... Hopefully the valve seals are ok as the AFR heads have only been on for 1 year.
I'm going to let it sit tonight, and then start it up tomorrow morning and see if it smokes. I'm hoping it was just oil left over from running it with no baffle. When I was installing the baffle, I flipped the upper intake over and back, and some oil actually came out of it.

One thing though. Is it ok if the PCV valve I'm using isn't the one the book says is for the car? Are all PCV valves the same, just different shapes and sizes?

Thanks again.....

Joe
Click to expand...

One other thing I wanted to mention. Per my mechanical oil pressure guage, I've got 50psi at idle, and 60-70psi cruising. Don't know if that helps the issue.

Thank you...

Joe
 

vristang

15 Year Member
Mar 31, 2005
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Aug 8, 2007
#6
  • Aug 8, 2007
  • #6
Oil system pressure shouldn't really affect crankcase pressure.
Unless you're running a vac pump.

If you picked up a pcv for your year Mustang, then you should be fine.
I doubt that is causing any issues.


Please keep us posted.

Hopefully, you just have some large puddles of oil left in the intake to flush out...

jason
 

pistonhead351

flim hunter
May 1, 2005
75
0
0
Aug 8, 2007
#7
  • Aug 8, 2007
  • #7
i added a second pcv valve and it made my car suck more oil and it raised my idle about 500 rpms. i got tired of oil in my upper intake so i just put breathers on my motor and plugged the pcv. works good now!
 

vristang

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Aug 9, 2007
#8
  • Aug 9, 2007
  • #8






 

daddystang

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Aug 13, 2006
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Aug 10, 2007
#9
  • Aug 10, 2007
  • #9
Just an update, had a little bit of smoke at startup this morning, but none while driving...that i saw.

A little bit of smoke also at startup this afternoon, but not as much as the first time. Still think there's a little bit of oil that needs to come out of the intake. I checked both PCV hoses, and they appear to be dry so im thinkin i'll just go with it for now and see if it works itself out. Thanks Jason for your help.

Joe
 

daddystang

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Aug 13, 2006
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Aug 13, 2007
#10
  • Aug 13, 2007
  • #10
I took off all the PCV hoses, and the fitting where they connect to the intake. The hoses were fairly dry, but I saw some oil still in the intake. I dried it out with a towel on a screwdriver the best I could. I had a little smoke yesterday morning, but none the remainder of the day. I'm going to start it when I get home today.

Just an update....

Thanks,
Joe
 

85_SS_302_Coupe

it sucks (I know) to be on the receiving end
15 Year Member
Nov 11, 2003
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Aug 13, 2007
#11
  • Aug 13, 2007
  • #11
Have you tried to pull out the PCV and then see if it smokes? That'll tell you if that's the cause of your smoke issue. If it doesn't smoke then it probably is the PCV, but if it still does i wouldn't worry about adding a second one because your problem is elsewhere.
 
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