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EFI PCV help what does everyone run?

  • Thread starter Thread starter 1987stangman
  • Start date Start date Jan 15, 2009

1987stangman

Member
Jul 12, 2006
684
24
19
Jan 15, 2009
#1
  • Jan 15, 2009
  • #1
Hello everyone. I am having a small oil consumption issue here that I would like to throw out and see if anyone has a viable solution to my problem. The stock PCV system does not seem to do it's job. When I had the motor out last October for the rebuild I noticed that there was a HUGE amount of oil in the upper intake that required me to suck out with a vacumme and alot of brake cleaner to remove the residue. Well now a few months later the problem has returned. From what I can tell the upper is collecting the oil from the PCV valve and then sending it though the intake to the cyl's. It has managed to foul nearly every plug. Last weekend I removed the upper and it had way too much oil inside the PCV vac line and inside the upper itself. I am stumped as to why the PCV system is not working right. I mean heck, 3 years ago the stock intake and PCV was working but when installed the Cobra the car started eating oil abnormally. Before I rebuilt the motor It was really bad and I chalked it up to 170K motor. Now that everything is new again this problem should not be there even with the ported heads and the ported lower intake.

I have read that this is somewhat a common issue but I need to find a resolution soon because this car is my DD. Any ideas guys?
 

90lxcoupe

20+ Year Stangneter
Oct 7, 2003
3,596
350
134
Jan 15, 2009
#2
  • Jan 15, 2009
  • #2
that dosent sound right... mabye your crankcase is pressurized?? which dosen't really make any sense.

If you want to get rid of the PCV the best way to do it is to buy/make a plug for the back of the intake, then weld a -12an fitting to the valve cover, and run the line to a catch can with a filter on it.

you can also use a push in breather, but the drawback to this is that the breahers sometimes fall out under hard acceleration, and they will land directly on the headers, which can cause a fire.

if i were you the first order of buisness would be to figure out why so much oil is getting into the intake... fords are known for bad PCV systems, but it sounds like something beyond that. there is no reason that it should be fowling the plugs.
 

strtrcr50

New Member
Jun 21, 2006
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Previously from Dirty Jerzey exit 7a
Jan 15, 2009
#3
  • Jan 15, 2009
  • #3
I have read about this before. I want to say there is supposed to be a baffle under the PCV valve on those cobra intakes. Did you install it? The chinese versions seem to be worse. Also, you can call FRPP tech line if you don't have the baffle and need it. 1 800 367 3788
 

1987stangman

Member
Jul 12, 2006
684
24
19
Jan 15, 2009
#4
  • Jan 15, 2009
  • #4
strtrcr50 said:
I have read about this before. I want to say there is supposed to be a baffle under the PCV valve on those cobra intakes. Did you install it? The chinese versions seem to be worse. Also, you can call FRPP tech line if you don't have the baffle and need it. 1 800 367 3788
Click to expand...

Yea, it is the chinese version and I did install a new baffle. This problem started before the rebuild and I lazely assumed it was bad valve seals, blow by, etc. But that is not the case now. I bet if I re-installed the OEM HO intake the problem would stop.
 

90lxcoupe

20+ Year Stangneter
Oct 7, 2003
3,596
350
134
Jan 15, 2009
#5
  • Jan 15, 2009
  • #5
it dosent make a hole lot of sense to me, mabye someone else will chime in...
 

strtrcr50

New Member
Jun 21, 2006
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4
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Previously from Dirty Jerzey exit 7a
Jan 16, 2009
#6
  • Jan 16, 2009
  • #6
Do you have the larger baffle?

http://forums.stangnet.com/671309-fords-fix-frp-cobra-intake.html
 

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riceslayer302

Banned
Oct 3, 2006
0
1
0
CT
Jan 16, 2009
#7
  • Jan 16, 2009
  • #7
i got a steeda oil seperator kit, but if your sucking alot of oil its probably something more serious
 

88mouse

New Member
Apr 18, 2007
630
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Mooresville nc
Jan 16, 2009
#8
  • Jan 16, 2009
  • #8
I'am having the same problem.

Last week I swap the pro products intake that was on the car out for a holley systemax, and still having the same problem.

Mine is burning 1 1/2 qt of oil a week.
 

TheRedBlur

Active Member
Jul 7, 2003
15
0
38
seattle
Jan 16, 2009
#9
  • Jan 16, 2009
  • #9
Maybe you have the baffle installed upside-down? I know some of the baffles are angled on the leading end, the angle should face the manifold, not the lifter valley. As you accelerate, the oil will go to the back of the valley, and if that baffle has the angled part facing forward and down, it will scoop oil up. You could also have a bad pcv valve?
 
T

thebullschmidt

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Dec 12, 2008
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Jan 16, 2009
#10
  • Jan 16, 2009
  • #10
heres what you do... go to lowes and go to the tool section and buy and water seperator for a compressed air system usally aroun 12 or 13 bucks... and buy some barbed fittings that will thread into it and put it in the PCV vaccume line it will filter out any oil that other wise would be sucked in to your intake... ive done it and it works fine. youll have to empty the oil out of it every so offten depending on how much it is sucking up.

Hope it helps
 

1987stangman

Member
Jul 12, 2006
684
24
19
Jan 17, 2009
#11
  • Jan 17, 2009
  • #11
thebullschmidt said:
heres what you do... go to lowes and go to the tool section and buy and water seperator for a compressed air system usally aroun 12 or 13 bucks... and buy some barbed fittings that will thread into it and put it in the PCV vaccume line it will filter out any oil that other wise would be sucked in to your intake... ive done it and it works fine. youll have to empty the oil out of it every so offten depending on how much it is sucking up.

Hope it helps
Click to expand...

Yea I have done some research on the net about this and it looks like quite a common issue for folks that have replaced the stock upper and lower with an aftermarket piece. I have considered this idea

strtrcr50: I took a lot of pics of my rebuild when I was doing it so I will try and dig up a pic of the lower but I am pretty damn sure that the baffle that mine came with is WAY smaller than that one in the pic you provided. When did FR make this change? I was thinking about ditching the cobra and going with an Ede RPMII.
 

strtrcr50

New Member
Jun 21, 2006
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Previously from Dirty Jerzey exit 7a
Jan 17, 2009
#12
  • Jan 17, 2009
  • #12
1987stangman said:
strtrcr50: I took a lot of pics of my rebuild when I was doing it so I will try and dig up a pic of the lower but I am pretty damn sure that the baffle that mine came with is WAY smaller than that one in the pic you provided. When did FR make this change? I was thinking about ditching the cobra and going with an Ede RPMII.
Click to expand...

I don't know. I just know I was reading about it. I think that baffle might be the same as is installed on the newer explorer. You can see the part number if you want to give it a try. The guy I linked to got his 11/06
 

vristang

15 Year Member
Mar 31, 2005
4,933
101
124
Seattle
Jan 17, 2009
#13
  • Jan 17, 2009
  • #13
Some things to look at...

1. put a vac/pressure gauge on the crankcase remove the pcv for this test. If you have a VERY strong vac signal, then you have a vac leak between a runner and the lifter valley.

2. There should be a large baffle under the lower intake. I have been able to make a smaller baffle work though.

3. There is also supposed to be a 'screen' under the pcv. It installs between the pcv and the baffle.

4. Do you still have the TB-Valve Cover hose installed? This is a critical part of the pcv system.

5. When the heads were worked, did they replace the valve guides and seals?


good luck,
jason
 
P

phutch11

Member
Nov 14, 2005
328
2
18
Jan 18, 2009
#14
  • Jan 18, 2009
  • #14
I've got the edelbrock rpm and have the same problem on a motor with less than 85k miles on it.

I put a stock ford pcv valve on it and the problem seemed to get a little better.

Good luck...

Posted via Mobile Device
 

1987stangman

Member
Jul 12, 2006
684
24
19
Jan 18, 2009
#15
  • Jan 18, 2009
  • #15
vristang said:
Some things to look at...

1. put a vac/pressure gauge on the crankcase remove the pcv for this test. If you have a VERY strong vac signal, then you have a vac leak between a runner and the lifter valley.

2. There should be a large baffle under the lower intake. I have been able to make a smaller baffle work though.

3. There is also supposed to be a 'screen' under the pcv. It installs between the pcv and the baffle.

4. Do you still have the TB-Valve Cover hose installed? This is a critical part of the pcv system.

5. When the heads were worked, did they replace the valve guides and seals?


good luck,
jason
Click to expand...

Today I got into the car to figure this out:

1. I have tested the VAC signal and it is withing spec.
2. I will be putting a new cam in soon so I will tackle the baffle issue then unless I decide to use another brand intake.
3. I bought a new screen when I rebuilt the motor.
4. TB valve cover hose it still there and is no different than stock
5. The heads are my original E7's and I had them worked by Thumper Pefromance. Everything was replaced.


Today I removed the upper and pulled the PCV hose off and removed the fitting from the upper. There was alot of oil in that tube. Even though the PCV valve was new I replaced it and the entire hose. I also installed a simple fuel filter between the PCV and the intake. It is a plastic clear filter that is easy to remove, examine, and change, and easy to see what or if any oil gets through and works well with the intake vac. I also removed and changed the plugs. And what I found was easy to tell that the PCV is at fault. Cyls. 3 and 4 and Cyls 7 and 8 plugs were severely oil fouled and all of which are at the back of the motor and are the closest the PCV system in relation to where the oil is collecting in the upper. All the other plugs looked perfect but were changed anyway.

When I finished the new motor the car ran VERY strong but about 3 weeks ago normal performance and agesssive attitude started suffering (no thanks to this PCV). After today the car runs perfect. Hopfully I am on the right track to fixing this problem!

I will let everyone know what the outcome is.
 

vristang

15 Year Member
Mar 31, 2005
4,933
101
124
Seattle
Jan 18, 2009
#16
  • Jan 18, 2009
  • #16
On item 1....

What are you calling 'within spec'?
I've never seen any specs on this.... what was the magnitude of your vac signal?
 
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