gas in intake mainifold (help!)

[kontinu1]

I am currently having issues with my air/fuel. I took some things apart and hereis what I found. The 91 explorer starts sometimes but usually idels rough and stalls. I took off the air filter hose off of the front the intake byt he throttle body. When I looked inside the intake manifold there was like 1/2inch of gas laying in the bottom. Now on the driver side of the car by the firewall there is a piece that comes off the intake manifold it has a bunch of vacuume lines attached. For example there was the brake booster one, one went to the air filter box, I think 2 were open, we just plugged them up (on the top and facing the back) then there was one facing the front of the car. That one ran to the engine somewhere towards the front of the engine, didn't have time to trace it. Now here is the problem I think. When I try to start the car gas shoots out this hose (A LOT). Which is why the intake manifold is flling up with gas. Should this be a air vaccume line and not a gas line?
My truck is off the road and I need it for work so any advise would be appreciated.

 

[shamaal]

This sticker should be on the front of your car by the hood release. Not shown is another vacuum line that goes over to a vaccum reservoir, on the passenger side. From my understanding of your description there may be one of two things happening:

One of the vacuum lines that goes to the front of the car is for the FPR (Fuel Pressure Regulator). See the attachment, my finger is pointing to it. The vaccum hose attaches underneath. Perhaps a failure in the FPR is leaking gas through the line into the vacuum manifold.

The other possibility is that there is a bad o-ring on one of the fuel injectors that is leaking gas which is being picked up in the vacuum manifold. It's difficult to tell from your description which end of the vacuum hose the gas is coming from. Repair entails removal of the upper manifold and removal of the fuel rail and replacement of the injector o-rings.

The fuel system is under pressure, exercise caution. You are correct in that the should be no open holes on the vacuum manifold (tree).

 

[shamaal]

Another possibility I just thought of peculiar to Explorers with automatic transmissions (mine's manual). Sometimes the modulator goes bad and sucks Automatic Transmission Fluid (ATF) up into the manifold. Are you sures it's gas and not ATF?
This type of failure is known for blowing off vacuum hoses.
Here's a thread that will lead to further discussion.
http://www.explorerforum.com/forums/showthread.php?t=157733&highlight=vacuum+transmission
Ask questions, this is a friendly forum

 

[kontinu1]

thanks for your help, it was the fuel pressure regulator, it went bad then forcing air through what was supposed to be the vaccume line.