For the past week my 87 Wolfsburg has refused to settle to the proper idle.
 Instead, it would sometimes settle at 2,000 RPM then fall a bit and rise
again.  I examined the operation of the throttle switch and found that the
accelerator cable, because of the low temperatures of late, about twenty
degrees, had contracted enough to keep the throttle from settling in the
fully closed position and thus preventing the idle switch from operating
properly.  Temperatures here in the middle of the country can reach extremes
(zero in winter and over one hundred in the summer).  A cable which may be
properly adjusted in the summer may be a little to tight in the winter.
Remember the rule of diagnostic parsimony, always look for the simplest cause
first.

Rico Dagastino
Munford, TN