mine does the same thing...
Please post answers to the list instead of P-MAIL = PLEASE. ;0)
During cold idle, I squeezed the top hose = on my auxillary
air regulator like I think the = Bentley manual says to do.
I haven't got a tach, but just = listening to the RPMs they
only drop a teensy bit, if = that.  Am I doing the test right
and what does this mean?