Gas AND Oil in Upper intake?

[Luvmy88]

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]

It happens to mine too

Check out my old post....

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

 

[87'GTstang]

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]

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]

new valve covers with chrome breather, capped the port on the TB

 

[Luvmy88]

If gas is getting into the upper, this would be a valve or timing problem maybe? I'm out of ideas - clueless

 

[jrichker]

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]

I will try that, thanks - I'm not sure if it was leaking before I put this new fp regulator on or not...

 

[Luvmy88]

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"