buick parkave

i have a 97 buick parkave everytime i start the car it run's great & after a while it shuts down & it seems like the engie is locked but if u take out the spark plugs & the spark plugs be soak with gas & when u clean them the car start's right back up but does the same thing all over again ,also the oil & gas is mixing like if i change the oil the oil turn a real like color & u can smell the gas in the oil & it turns to a light carmal color & it's getting to much gas can somebody help !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! !!!!!!! :loser: me :screwy: :banghead: :banghead: :banghead: :banghead: :banghead: :banghead: :banghead: :banghead: :banghead: :banghead: :banghead: :banghead: :banghead: :banghead: :banghead: :banghead: