Booster

[Randy Mueller]

Jay, There are 3-things that will turn on the "RED" Brake Warning Light of the Hyd. System, Low Hyd. Fluid, Low Brake Fluid or Low Hyd. Pressure (or Bad Pressure Switch), You can Disconnect each wiring connector one by one until you find what Sensor(s) is/are causing the Warning Light to Come On...
As far as "Spongy" Feel of the Brake Pedal Goes, If the Engine is Running & Not Moving That is the Way the Pedal Feels if there is no Air in the System, For a Proper Test of how it Feels, Go for a Drive... Chances are Your ABS (if Operational) will Activate or Lock Up the Tires before you Feel any Sponginess... 
I have been Wrenching Professionally since 1974  & On Audi's since 1979...
The Hyd. Assisted Braking System was introduced on the Group 44 Chassis in 1984 & a Common Customer Complaint was that the Brake Pedal "Felt Spongy" (When Vehicle Not Moving) as You Stated...

Later, Randy
3Zero3 Motor Sports


________________________________
 From: Jay Kempf <jkempf at madriver.com>
To: 200q20v at audifans.com 
Sent: Tuesday, July 31, 2012 1:06 PM
Subject: Booster
 
Still fighting what I think are brake hydraulic issues. Finally got the car
out on the road and am working it back to health. When I first put it back
together and was going through systems I had no hydraulic pressure light and
no airbag light. Now both are back. Have to chase some mouse eaten wires
still but my brake pedal just started going spongy again and I had a lot of
free play. I think that is coming from the hydraulic booster. Anyone have
one they want to part with? Or both MC and booster? Might as well get some
spares for rebuilding. The person I was sourcing seals from for the MC
backed out so I still haven't gotten through on that project. I have the
master cylinder apart in the garage and measured but still no solid source
for seals. BMW guys are rebuilding the hydraulic booster with an oring pack.


jfk

_______________________________________________
200q20v mailing list     http://www.audifans.com/mailman/listinfo/200q20v