What is the fix for puff of smoke and wailing sound when started

[NYCSterling]

Hey Folks of the board!
I have searched and read and read and searched on the topic of the 4.4i puff of smoke when accelerating after a bit of idling.

Here are the details -
- does not smoke continuously
- did oil change
- changed PCV valves (those 2 red caps thing at the left and right of the engine)
- did a LiquiMoly engine flush


So all can seem well for a bit... no smoking.. then puff ! i get a lot if i am idling in slow traffic and then pull off..

I do not think that this is the valve seals or else it would have been continuous, right?

SOmetimes when i start first time there is a whistling/wailing - sounds like a loose belt...

If i turn off and restart it goes away.


Please... help