Weird CC fan behavior

[Henry A Harper III]

>
> Recently had the AC (R134 retrofit) serviced.

Red herring, very clever ;)

> Since then, the cc blower fan seems to only come on when it wants to...

Sounds like classic intermittent blower motor brushes in need of replacement
to me, is this still the original blower for that car? You can check for
full voltage (fan set to HI) at the blower connector, maybe whack the blower
while you are in there and see if it helps.

HTH
Henry Harper
http://www.henry-harper.com  hah at alumni.rice.edu
1991 200 quattro, 120k, one blower (and heater core) replaced, running R12
after Autofrost leaked out
1988 GTI 16v, 249k, still original blower & heater core, running R134a after
Autofrost leaked out