5K turbo boost question

[ti@amb.org (Ti Kan)]

Hey list,

I was driving my 84 5KT this weekend and noticed an anomaly.  The
car has the KH motor and is all stock except for a Charlie Smith
wastegate spring.  Normally I can easily reach 1.5 bar on the readout on
full throttle, but yesterday while driving on the highway I tried to
pass some cars and noticed that I was only able to attain 1.1 bar.
Several more attempts at getting more boost failed to go higher than
that.  After about an hour more of driving (without shutting off),
I tried again and got 1.5 bar reliably.  I didn't notice the fault light
come on at all, BTW.

So, what could cause the car not to reach full boost for a while
and then have it come back to its glory later?

-Ti
96 A4 2.8 quattro
84 5000S 2.1
80 4000 2.0
-- 
    ///  Ti Kan                Vorsprung durch Technik
   ///   AMB Research Laboratories, Sunnyvale, CA. USA
  ///    ti@amb.org
 //////  http://metalab.unc.edu/tkan/
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