I don't mean to be the messenger of bad news here but the problem you are describing is EXACTLY what happened when my 2.5 blew. She was running rough at idle when I went to gas her up....so I opened the hood, and when I went to check the oil there were puffs of smoke (water vapor) out of the dipstick tube. I went to check the air filter and it was pretty soaked in oil as well as the bottom of the air filter box. After a teardown it was found that my #4 cylinder broke both rings and scored the skirt. That's where all of the blowby oil was coming from.

Oh, and I couldn't get that #4 cylinder to fire for anything. Compression was very low also.