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Gas AND Oil in Upper intake?

  • Thread starter Thread starter Luvmy88
  • Start date Start date Apr 7, 2004

Luvmy88

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Oct 27, 2003
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Apr 7, 2004
#1
  • Apr 7, 2004
  • #1
I have recently put my stang back together, and have been having idling problems. I removed the upper intake to check the injectors, and I noticed a large amount of oil/gas mixture towards the rear of the intake. What does this mean? Both in the upper and lower intake, looks liek only the last 2 or 3 runners.

Most everything on the top of my motor is new. Found this oil/gas with only 178 miles on this new engine. PCV valve is new as well.

Help, what should I be looking for when trying to track this down, and prevent the leaking.
 

BlackFox5.0

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Aug 7, 2000
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Apr 7, 2004
#2
  • Apr 7, 2004
  • #2
It happens to mine too

Check out my old post....

http://forums.stangnet.com/showthread.php?t=428118
 
8

87'GTstang

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Feb 16, 2004
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Apr 7, 2004
#3
  • Apr 7, 2004
  • #3
That essentially means that your intake valve guides are worn or more likely, your valves are not seating correctly on your heads. I find it funny it happening on your engine, you saying it's new and all. Generally that's associated with all-around worn out engines with high mileage. The oil is somehow making it past your piston rings and is then blown past your intake valves -> your crappy idling issue. Did you by any chance get a valve job done on the heads, are they the original heads, aftermarket, or when you say most up top is new that they are new also?
 

Luvmy88

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Oct 27, 2003
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Apr 7, 2004
#4
  • Apr 7, 2004
  • #4
Yes, freshened up the heads, $1000 worth of head and block work.

What if the rockers werent torqued down correctly?

Looks and smells like more gas than oil thats for sure.
 

Luvmy88

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Oct 27, 2003
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Apr 7, 2004
#5
  • Apr 7, 2004
  • #5
new valve covers with chrome breather, capped the port on the TB
 

Luvmy88

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Oct 27, 2003
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Apr 8, 2004
#6
  • Apr 8, 2004
  • #6
If gas is getting into the upper, this would be a valve or timing problem maybe? I'm out of ideas - clueless
 

jrichker

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Apr 8, 2004
#7
  • Apr 8, 2004
  • #7
Gas in the upper - possible leak in the vacuum side of the fuel pressure regulator. If the fuel pressure regulator has a pinhole leak in the diaphram, it will suck gas into the vacuum line and then into the upper manifold. Remove the vacuum line from the regulator & with the car running, look for gas to come out of the vacuum port on the regulator.
 

Luvmy88

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Oct 27, 2003
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#8
  • Apr 8, 2004
  • #8
I will try that, thanks - I'm not sure if it was leaking before I put this new fp regulator on or not...
 

Luvmy88

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Oct 27, 2003
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Apr 8, 2004
#9
  • Apr 8, 2004
  • #9
It appears only the last two or three runners on the intake have gas in them... soaked the upper/lower gasket right there where the last two runners "meet"
 
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