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PCV routing question

  • Thread starter Thread starter dniksich
  • Start date Start date Mar 21, 2021
D

dniksich

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May 10, 2020
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Mar 21, 2021
#1
  • Mar 21, 2021
  • #1
I'm working on a 2003 4.6 with a P1SC on it and I'm trying to figure out a few vacuum/pvc lines since the passenger side isn't even hooked up and had a huge vacuum leak and is causing a lot of oil to be pulled from the drivers cover into the throttle body. This is the way it's hooked up now and I need info on what is wrong here. The IAC is connected to the intake piping for the SC, Drivers side valve cover is connected to the nipple to the right of the IAC on the throttle body and the pass side isn't hooked to anything? I've been searching for any help but haven't found anything yet. Thanks for any help!
 

Dark04GT

10 Year Member
Apr 27, 2008
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NC
Mar 22, 2021
#2
  • Mar 22, 2021
  • #2
dniksich said:
I'm working on a 2003 4.6 with a P1SC on it and I'm trying to figure out a few vacuum/pvc lines since the passenger side isn't even hooked up and had a huge vacuum leak and is causing a lot of oil to be pulled from the drivers cover into the throttle body. This is the way it's hooked up now and I need info on what is wrong here. The IAC is connected to the intake piping for the SC, Drivers side valve cover is connected to the nipple to the right of the IAC on the throttle body and the pass side isn't hooked to anything? I've been searching for any help but haven't found anything yet. Thanks for any help!
Click to expand...
Having it connected to the intake causes positive pressure to enter the crankcase (not what you want).

The easiest solution is to go to a passive solution. I’d disconnect the PCV system from the intake (block off the ports on the intake). Run lines from each of the valve covers to a catch can (mine connect together with a brass T connector right before the catch can). On the discharge side of the catch can run a line with a small cone air filter on the end to allow for ventilation.

I have this catch can - works great and has an easy valve for cleaning:

Moroso Mustang Air-Oil Seperator (99-04) GT 85486 - LMR

Moroso just released their new aluminum Oil Separator for your 1996-2004 Ford Mustang 4.6L!
lmr.com
 
Last edited: Mar 22, 2021
D

dniksich

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May 10, 2020
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Mar 22, 2021
#3
  • Mar 22, 2021
  • #3
Thanks! That's what I'll do.
 
D

Dubsport

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Dec 24, 2020
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Edmoton, Alberta, Canada
Mar 23, 2021
#4
  • Mar 23, 2021
  • #4
The pcv should be hooked up to throttle body still but the breather hose should not be on the pressure side but to the intake hose for the supercharger if that makes sense... If I remember I will take pics of mine
 
D

dniksich

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Mar 24, 2021
#5
  • Mar 24, 2021
  • #5
Dubsport said:
The pcv should be hooked up to throttle body still but the breather hose should not be on the pressure side but to the intake hose for the supercharger if that makes sense... If I remember I will take pics of mine
Click to expand...
I'm assuming you mean before the supercharger so it's not under boost? Yes though, a pic would be good. I did order a catch can. Thanks
 
D

Dubsport

Member
Dec 24, 2020
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Edmoton, Alberta, Canada
Mar 24, 2021
#6
  • Mar 24, 2021
  • #6
Correct!
 
D

dniksich

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Mar 25, 2021
#7
  • Mar 25, 2021
  • #7
Damn, that might be a problem since room was scarce with the radiator in it, the only air filter setup I could use is a cone style right on the supercharger with no piping. Unless it's ok to tap right off of that with a nipple for it?
 

Dark04GT

10 Year Member
Apr 27, 2008
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Apr 2, 2021
#8
  • Apr 2, 2021
  • #8
dniksich said:
Damn, that might be a problem since room was scarce with the radiator in it, the only air filter setup I could use is a cone style right on the supercharger with no piping. Unless it's ok to tap right off of that with a nipple for it?
Click to expand...
The amount of vacuum before the supercharger is not worth it IMO. I let it passively vent to the atmosphere and change my oil regularly.
 
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