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PCV problems

  • Thread starter Thread starter AUBURN1111
  • Start date Start date May 15, 2009

AUBURN1111

Founding Member
Oct 17, 2000
560
20
49
Mobile, AL
May 15, 2009
#1
  • May 15, 2009
  • #1
Cant seem to get the PCV valse to seat tightly even with a new gromet. I also have a problem sucking oil through it and into the upper intake.
What can I try to resolve this?
 

95Vert383AOD

15 Year Member
Jun 10, 2008
1,133
34
69
New Bedford, MA
May 15, 2009
#2
  • May 15, 2009
  • #2
Can you get a picture of the PCV grommet? Also valve cover breather lines connect on the intake pipe or before the throttle body and pcv connects after throttle body (directly to plenum)
 

AUBURN1111

Founding Member
Oct 17, 2000
560
20
49
Mobile, AL
May 15, 2009
#3
  • May 15, 2009
  • #3
Connected as typed above all stock motor so I dont believe thats the problem. The grommet is one that I ordered from Advanced Auto Parts looked the same as the one I pulled out, sorry no pics.
 

95Vert383AOD

15 Year Member
Jun 10, 2008
1,133
34
69
New Bedford, MA
May 15, 2009
#4
  • May 15, 2009
  • #4
Well its not going to be super tight. But as long as its seated all the way down you should be ok. Oil in the intake can be caused by a vacuum leak elsewhere in the vacuum system as well.
 

HISSIN50

"How long does it take to get help in here?
15 Year Member
Nov 29, 1999
31,179
33
129
May 15, 2009
#5
  • May 15, 2009
  • #5
If you use a Motorcraft PCV valve, it should fit tight. Aftermarket valves can fit loose.

Oil in the intake and the fact that you're messing with your PCV suggest a lack of ring seal. This can be normal for low-tension rings with miles on them. An oil separator can help with the situation.
 

AUBURN1111

Founding Member
Oct 17, 2000
560
20
49
Mobile, AL
May 15, 2009
#6
  • May 15, 2009
  • #6
Only 30,000 on a complete rebuild with DSS internals, I might try the motor craft PCV. What is this oil seperator and where do I find one?
 

HISSIN50

"How long does it take to get help in here?
15 Year Member
Nov 29, 1999
31,179
33
129
May 15, 2009
#7
  • May 15, 2009
  • #7
Unless you just did a leakdown you don't know what's going on in the motor, regardless of mileage.

For the separator, I just use an air tool air/oil separator with the element removed. It's more of a catchcan like this, but it's effective. There are a zillion different ways to do it. I went with the 20 dollar way.

Good luck.
 
B

brecht63

Member
Jun 11, 2002
45
0
6
May 17, 2009
#8
  • May 17, 2009
  • #8
Did you by chance put a HV pump in it? Had the same issue with mine after I had it out and rebearinged it and replaced the oil pump with a high volume because of very loose crank tolerances and worn lifters. I just plugged off the PCV system and put a breather cap on it. problem solved, till I put a standard pump back in. I'm thinking its throwing too much oil around up top because of the HV pump and sucking it out the PCV (FYI-a cobra upper plenum holds half a quart of oil), it didnt do it before and the only change was the pump. suprisingly it has hardly any blowby, great compression and uses no oil and has just under 200,000 on it.
 

AUBURN1111

Founding Member
Oct 17, 2000
560
20
49
Mobile, AL
May 18, 2009
#9
  • May 18, 2009
  • #9
you dont have problems blowing out the front and rear lower intake gaskets, I already have a breather cap
 

vristang

15 Year Member
Mar 31, 2005
4,933
101
124
Seattle
May 19, 2009
#10
  • May 19, 2009
  • #10
AUBURN1111 said:
you dont have problems blowing out the front and rear lower intake gaskets, I already have a breather cap
Click to expand...
Then why are you running a pcv?

With EFI, you run a CLOSED pcv system OR you run breathers.... not both.
Running both creates an effective vac leak via the breathers.



JT (Hissin50) recommended a leak down test... I would add a compression test to that as well...
All we can do is suggest things for you to check. It is ultimately up to you to go perform these tests, and report back with quantitative data.

Check for baffles in lower intake, under the pcv... as well as in the valve cover in the filler neck.

Is the hose running from the filler neck to the Throttle Body still in place?
 

AUBURN1111

Founding Member
Oct 17, 2000
560
20
49
Mobile, AL
May 19, 2009
#11
  • May 19, 2009
  • #11
I will report back just been busy, thanks for the suggestions. I do have the vacuum line connected from the throttle body to the oil filler neck. Baffles under the valve covers are still in place.
 
B

brecht63

Member
Jun 11, 2002
45
0
6
May 20, 2009
#12
  • May 20, 2009
  • #12
If you have a breather cap you have to cap off the line from the TB and the filler neck and the vac line going to the pcv on the intake side. If you dont you will have un-metered air going into your engine by way of your PCV. what about lower intake gaskets?
 

AUBURN1111

Founding Member
Oct 17, 2000
560
20
49
Mobile, AL
May 20, 2009
#13
  • May 20, 2009
  • #13
will try capping those off, upper and lower gaskets are good recently replace and car ran fine.
 
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