Karl,
    I live in the mountains near Yosemite National Park. It can get rather cold here... I'll save your post to my personal archives and give it a whirl when the temps drop. 

                    Thank you,  Mtngal
  Subject: Is my 84 Vanagon Aux. Air Regulator busted?
  Sorry I didn't get back to you earlier.  I live in Phoenix, AZ, and was told that here in the summertime the effect on the idle is negligible, since at ambient temp the AAR has almost no effect.  Seems you have to be below 40 - 50 degrees and the engine entirely cold to perform this test.
  Karl Wolz
      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?

[text/html]