For the quick fix, you don't need to remove the tank and airbox -- just get down on the right side of the bike, look in between the frame rails behind the cylinder head, and find that little rubber accordion boot. A flashlight might help. It's a few inches in and tucked slightly upwards. Once you've found it, take a can of WD40 (with the straw attached) and shoot a little at the rod coming out of the accordion boot. Then cycle the ignition on and off and wait the 30 seconds for the stepper motor to reset -- might be worth watching the process and listening for the sound to see if it's the same as it usually is (I noticed that the two times I had the idle problem, it was preceded by the stepper motor making a different noise from the usual).