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  • 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk-

Fox Too much vacuum or what

  • Thread starter Thread starter 92lxssp5speed
  • Start date Start date Jul 12, 2022
9

92lxssp5speed

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May 22, 2022
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KcMo
Jul 12, 2022
#1
  • Jul 12, 2022
  • #1
92 5.0 gt40heads 351cam trick flow rollers Holley upper and lower intake bbk from filter to the mufflers new pcv and it's still sucking oil into intake enough that it runs out the throttle body and out the air filter and twice now it's blown a cloud of smoke on startup I'm sure if I stayed out of the pedal it wouldn't do that but I can't stay out of the gas pedal but I don't see that as being my solution
 
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92lxssp5speed

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May 22, 2022
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KcMo
Jul 12, 2022
#2
  • Jul 12, 2022
  • #2
The car is far from ratty or

clapped out
 

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90sickfox

Wasn't a pretty sight...and I've got big hands
SN Certified Technician
Mar 2, 2015
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Jul 12, 2022
#3
  • Jul 12, 2022
  • #3
Sounds like you need an oil catch can. Some intakes don't have a separator plate on the bottom of the lower intake. Without one it will suck oil instead of just oil vapors. The catch can goes in the hose between the intake and the pcv valve.
 

rednotch

I'd like to remain having one chocolate starfish
Founding Member
Aug 14, 2000
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south jersey
Jul 12, 2022
#4
  • Jul 12, 2022
  • #4
The Holley intake was all ways bad with sucking oil from the valley, used a later explore style baffle under the pcv on mine but it also has breathers on both valve covers on that car. It's mostly from the location of the vaccum source on the upper intake since Holley has it right at the throat it puddles oil there.
 
Last edited: Jul 12, 2022
Reactions: 92lxssp5speed

TOOLOW91

If you're the village idiot what's that make me?
20+ Year Stangneter
Nov 29, 1999
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S.I.NY
Jul 12, 2022
#5
  • Jul 12, 2022
  • #5
If it’s a systemax they are known for this .

Does it have the baffle under the pcv ?
 

Mustang5L5

That is…until I whipped out my Bissell
Mod Dude
Feb 18, 2001
43,200
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Massachusetts
Jul 13, 2022
#6
  • Jul 13, 2022
  • #6
You might need something like this

https://lmr.com/item/OSC-3045PB/mustang-jl-oil-separator-passenger-side-black-86-93
 
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9

92lxssp5speed

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May 22, 2022
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KcMo
Jul 14, 2022
#7
  • Jul 14, 2022
  • #7
TOOLOW91 said:
If it’s a systemax they are known for this .

Does it have the baffle under the pcv ?
Click to expand...
Yes and yes
 
9

92lxssp5speed

New Member
May 22, 2022
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KcMo
Jul 14, 2022
#8
  • Jul 14, 2022
  • #8
Thank you all appreciate the hell out of it
 

TOOLOW91

If you're the village idiot what's that make me?
20+ Year Stangneter
Nov 29, 1999
8,481
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S.I.NY
Jul 14, 2022
#9
  • Jul 14, 2022
  • #9
92lxssp5speed said:
Thank you all appreciate the hell out of it
Click to expand...
Oil separator for sure in the pcv line will help immensely
 

7991LXnSHO

wanna catch the space herp
10 Year Member
Sep 1, 2010
7,387
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Kearney, NE
Jul 14, 2022
#10
  • Jul 14, 2022
  • #10
Now a silly answer - too much vacuum is when the carpet gets sucked out of the car with the dirt.
 
Reactions: General karthief and TOOLOW91

manicmechanic007

5 Year Member
Sep 26, 2017
2,526
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Roy, Utah
Jul 16, 2022
#11
  • Jul 16, 2022
  • #11
All good answers
I would run a crank evac system on yours
The reversion they call it is what is putting the oil in your intake
Reversion happens during the time when both valves are open
Part of the scavenging effect
A few ways to control this
Crank evac, catch can, ribs in the floor of the plenum
Good luck
I get a kick out of Smoky Yunick's 302 Chev setup with the big steelies
 

General karthief

wonder how much it would cost to ship you a pair
5 Year Member
Aug 25, 2016
27,857
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polk county florida
Jul 16, 2022
#12
  • Jul 16, 2022
  • #12
Blow by?
Know how many miles on the block?
Is it blowing smoke out of the oil fill tube or dip stick tube?
 
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