Vacuum-leak question...please clarify

[quk@isham-research.demon.co.uk (Phil Payne)]

In message <0716D052C1CFD0119D280060979FBE9A0D5FCF@a1.matrix.com.pl> Aleksander Mierzwa writes:

> Vacuum leaks create lean condition. When you have no vacuum leaks
> removing the disptick will cause the engine to run lean, but not enough
> to make it stall. If you already have vacuum leaks, the additional leak
> through the dipstick makes it run so lean it stalls.

Well, the vacuum leaks actually create a _rich_ condition, in a way.
 
What happens is that the tech who sets up the car dials in a richer setting to 
compensate for the leak.  Audi, BTW, _insist_ that the breathers be 
disconnected and plugged.  But if the car already has a large leak, the mixture 
will have been set rich to get an acceptable idle CO value.  Adding more leak 
to an existing leak makes less difference than adding leak where none was 
before.

-- 
 Phil Payne
 Committee Member, UK Audi [ur-]quattro Owners Club