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Vacuum Pump experiment

Wanting a definitive answer about the brake performance with a "disabled"
vacuum pump I took out the cam actuated rod.  After my brief test drive I
determined that the vacuum pump for the vacuum assisted brakes has no
functional pupose.  The brakes felt absolutely the same as before.  I
don't understand why this is though.  In the manual it says that if the
engine should die for any reason while the vehicle is moving there should
be enough brake "assist" left to easily stop the vehicle once.  I tested
this (rod in place)and sure enough if you kill the engine and hit the
brakes they feel normal, but if you let your foot up then hit the brakes
again the pedal
is dead hard and it requires the strength of Thor to stop the car.  Now
logically I would think that shutting off the motor stops the vacuum pump
from working therefore deleting the power assist to the brakes.  Now why
in the name of the Audi gods do the brakes still feel fine with the rod
removed? Next question:  without the rod in place could there be any
danger in "excess" amounts of oil collecting in the pump?

Brendan Rudack			rudack@ucsub.Colorado.EDU
'88 90Q
Fenton, Michigan USA