gmc sonoma has gas in oil HELP!!?

[aron ft]

i had done a compression check today on my gmc sonoma ( 4.3l v6 1994 ) and cylinder 4 is at 120 pounds and the others are at 155, what could cause that? and the oil had about 2 quarts of gass mixed in it, what is wrong?
to : dangerll.. could it be because a valve is not ceeting all the way?

 

[Molson02536]

Could be bad valve guilds and bad compression rings on the #4 piston, and your fuel pressure regulator may be leaking gas or your fuel injector nozzle to #4 cylinder. How is the engine running and what kind of smoke is coming from the exhaust if any???? Keep me posted. Try cleaning your intake track with Sea foam, just follow the instructions on the can, and yes there will be lots of smoke. Do a search on Youtube and you'll see what smoke I'm talking about. This should help clean any carbon build on your valves. Good luck and have your fuel pressure regulator tested for any leaks which you can do by doing a fuel pressure leak down test. Good luck and keep us posted.