[urq] Cruise control

[Brandon Rogers]

Guys-
OK so over the weekend I grounded the vacuum pump and I could see it trying 
to compress the CC diaphragm - but it didn't do enough to move the throttle. 
So I manually compressed the diaphragm and then started the pump - the pump 
could not hold it in place.  So I'm thinking either I _do_ have a vacuum 
leak of a weak pump.  I have another pump - plugged it all - same thing. 
Must be a leak.  My diaphragm itself is leak free - that I'm 100% sure.  So 
I guess I have another leak elsewhere.  I even used a stethoscope (with a 
2.5mm hose as the "pickup")  and listened all around the sytstem with the 
vac pump motor running - could not hear a leak anywhere.  Vac Vent Valves 
are adjusted so the plungers are totally compressed when the pedals are in 
default position.

Any other ideas?  Should I just replace the vent valves?  What else could it 
be?

Thanks-

Brandon

----- Original Message ----- 
From: "Buchholz, Steven" <Steven.Buchholz at kla-tencor.com>
To: "Brandon Rogers" <brogers at terrix.com>
Sent: Friday, July 08, 2005 2:30 PM
Subject: RE: [urq] Cruise control


... the same thing you did ... squeeze the air out of the piece that
pulls the throttle ... that's the vacuum motor ...

I've never tried running the pump ... that should give a complete test
that the system can hold a vacuum ...

Sorry for the confusion!
Steve

> -----Original Message-----
> From: Brandon Rogers [mailto:brogers at terrix.com]
> Sent: Friday, July 08, 2005 12:38 PM
> To: Buchholz, Steven; Urq List
> Subject: Re: [urq] Cruise control
>
> Steve-
> I'm not sure what you mean by "manually compressing the vacuum motor"
could
> you please clarify.
>
> If I ground the line to the vac pump and make it run - will it cause
the
> diphragm to compress?
>
> I did the tests on the vacuum motor per Bentley and it did pass - ie
it ran
> when grounded and the vent valve clicked when grounded.  I do have
another
> vac pump that I installed a while back (and took back out) that did
not make
> the CC operable.  I can test it too.
>
> Thanks for the help
>
> Brandon
>
> ----- Original Message -----
> From: "Buchholz, Steven" <Steven.Buchholz at kla-tencor.com>
> To: "Urq List" <urq at audifans.com>
> Sent: Friday, July 08, 2005 12:44 PM
> Subject: RE: [urq] Cruise control
>
>
> Yes and Yes ...
>
> ... the proper test is to pull the vacuum line from the CC pump and
> apply suction there ... and you can do this by manually compressing
the
> vacuum motor or by using an external vacuum pump ...
>
> ... if anything the dual filament bulb holders help ... you've got two
> more high current filaments in parallel to ground ... and the aux
ground
> strap would help mediate any resistance in the ground path proper ...
>
> I don't remember from your original post ... have you tried a known
good
> vacuum pump?
>
> Steve B
> San Jose, CA (USA)
> >
> > So you're saying if the brake/clutch vent valves were not properly
> adjusted
> > then the CC diaphragm would not stay compressed if I were to
manually
> > compress it?  Per Bentley I unhooked the vacuum line to the pump and
> > compressed the diaphragm, and capped the open tube with my finger,
the
> > diaphragm did not expand back to normal.
> >
> > Will the dual bulb holders (rear brake lights) affect anything here?
> I did
> > also add a ground strap for each side.
>
> _______________________________________________
> Audifans urq mailing list
> Send posts to: mailto:urq at audifans.com
> Manage your list connection:
http://www.audifans.com/mailman/listinfo/urq
> Have an urq question?  Check the Audifans Knowledgebase!
> http://www.audi-quattro.org/cgi-bin/twiki/view/Audi/UrQuattro
> Have an urq answer? ... Please help others by adding to the KB ... all
> contributions welcome!