thatswhoiam

started about a month ago, at first was intermittent, but doing almost all the time now. when its in park it idles up and down and makes a noise that sounds like a drum roll in the distance or like a clothes dryer running without the discharge hose attached/ a muffled rumbling noise that seems to be coming from what seems like the intake area ( by drivers side ) . its much louder than what is heard on this video, it causes a scene. and its getting louder.. tonight while in the drive thru line and in park, the rpms went much lower than what it usually does and seemed like the engine was going to stop. no noticeable loss of power while driving, no check engine light. air filter is about a couple years old and its clean. its a 2001 supercrew 5.4 triton , has approx 109,000 miles. noise doesnt seem to be affected by accelerating /decelerating. used to appear after driving for a few minutes, but now it starts soon after starting engine.

https://photos.app.goo.gl/YV5rGTiDFYxDg42B8

white89gt

Run it for codes. Doesn't matter if the light is on, check it anyway.

Jbrew

Sounds like a hole or crack in the PCV line or elbow.

Switch your heater to off or vent, does it still happen ?

If the above check out, IAC problem I expect.