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Weak Brakes

Mike D. posted a comment about his brakes....and listed symptoms.

Mike, your symptoms show the classic failure of a pressure 
accumulator (PA).  You must have just joined the list, as I've agonized 
over mine recently.

If you had an Audi place check your car and they DIDN'T even check 
the pressure accumulator (aka: da bomb) then don't go back.  They're 
incompetent and probably dangerous.   The highb raking effort and 
brake warning light on are definitive indications of this part's 

The PA/bomb is located just inboard of your left front wheel.   It is 
a pressure regulator for the hydraluic assist system which aids in 
both boosting braking and providing power steering assist.  It is a 
totally saprate system from your brakes - and uses a different fluid 
called Pentosin (a special synthetic fluid).  It's called da bomb 
'coz (I think) it looks like a WWII German potato masher grenade.  
It's a metal bottle with pressurized nitrogen inside.

If you're handy with wrenches, you can replace the pressure 
accumulator in about an hour.  Doing this will require about one 
liter of Pentosin at  $20.  A shop can also do this easily....but 
don't pay over an hour's labor, as I've done it twice 
in my garage in less time than that.  The high pressure line into da 
bmob has a banjo fitting which may have (depdnign on your model) 
metal washers or rubber O-rings.   It's preferable (but not imperative) 
to replace the washers when doing this job if you have that model.  
The O-rings seem to tolerate re-use with no problem.

If you want to do it yourself, email me direct and I'll send you the procedure 
which other kind folks on this list sent to me in my time of  

********** A Washington State Cougar in Aggieland (aTm) **********

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