Annoying Engine Tapping (SMTP Id#: 37151

[stephenm@ix.netcom.com (Steve Manning)]

>Jeremy, my 4kcsq has this vacuum assist unit on it also.  I have
>taken the push rod out and left it out.  I have not noticed any
>difference in stopping power.
>
>I can't tell you what to do.  But if it was me I would take the
>push rod out and leave it out.  I know for a fact that are a
>number of audies out there running without the push rod in place.

Maybe I'm just too cautious, but I would NOT disable the vacuum pump.  Audi
installed the pump to ensure there was always enough vacuum to power the
brakes, ensure a consist idle, etc. under all conditions.  Who wants to take
the chance of running out of vacuum assist for the brakes when you least
expect it (and trust me, braking w/o the assist on system that should have
it is not fun!).  As an old hot-rodder, I've had to put vacuum pumps or
vacuum canisters on big ol' American V8's when the camshaft was fairly
radical (too much valve overlap at idle = little vacuum).  Seems to me that
you could run out of vacuum pretty quick going from full throttle (little
vacuum) to full brakes (full vacuum required) a few times (like on the
track?)...........SLM