I have a 2003 with a 4.7.It won't idle at all in the cold.Thought it was just abit of dirt or moisture freezing up in the cold.-18 here .take off breather tube from crankcase and a bit of water comes out.Pull idle valve and a lot comes out.Where is it coming from?Had head gaskets replace two months ago.Any ideas are appreciated

 

Sounds like you have a bad PCV valve and/or the vac hose from the PCV valve to the intake is clogged.

 

I have the same exact problem. 2004 4.7, halfway through last winter it started not idling in cold weather. I would have to sit there and gas it until it warmed up enough to idle on it's own and sometimes it still wouldn't run, so I'd "power brake" it everywhere. Last summer it ran like a champ.
Come this winter, same thing. PITA, but I just went with it. 2 weeks ago driving down the Hwy, the throttle stuck open. It wouldn't drop below 2000 RPM, it was like scary cruise control. I forced it to a stop and it automatically red lined. I shut it down and restarted it, went red line right away. I had it towed to a shop and they changed the IACV. Got it back and it ran like a champ until yesterday.
Yesterday I noticed it would jump from 500 to 1100 RPM's, I hoped it wasn't anything and drove home. This morning was same old crap as before, wouldn't idle on it's own. Drove to work anyway and the throttle stuck open again, I stopped, red line, shut down. This time I manually snapped the throttle on the TB closed. Drove straight to Midas.
They said my throttle plate was iced up and sticking and the IAC was completely encased in ice. They were baffled as to why and did a full inspection. All they could come up with was my K&N CAI was maybe causing water to condense inside the intake tube. All they said was to go back to a stock intake, possibly insulate the intake or look on the internet to see if anyone else has had this problem. I live in Alaska and don't have any warm storage for it. This sucks. I'll try to insulate the intake tube with high temp foam tonight and see what happens

 

My PCV valve on my '03 was totally clogged along with the lines from the heads. I had several idle problems, but I live in TX so it doesn't get too cold here. After cleaning everything it was better, but ultimately had to change the throttle posistion sensor as well. You are definitely getting condensation from somewhere though.

 

I'm having the exact same problems, but I haven't redlined yet...so I keep clutchin' it everywhere/ powerbreakin' it. I also have a CAI, my intake tube is metal though *poormans intake* Last winter I didn't have this problem, but also didn't have the CAI.