I've read the masses of topics regarding DIY Solenoid Cleaning and would still like a little more input:

2006 530i with an N52 engine

-So the symptoms are rough idling, loss of power, low MPG?
-Anything with oil consumption possible?
-Would the loss of power cause hard 1-2 shifting/2-1 downshifting? Jolts?

As for the procedure, is re-initializing the solenoids via INPA necessary? The DIY don't really mention it, neither does Bentley.

 

which solenoid are you referring to?

Are you referring to Intake Manifold adjuster valve?

 

Sorry about that: I am referring to the VANOS solenoids on the front of the engine connected behind the camshaft position sensors
http://www.e90post.com/forums/showthread.php?t=486201