Re: [T3] Rpm drop

[Jim Adney <jadney@vwtype3.org>]

On 24 May 2007 at 11:22, John L. Morgan IV wrote:

> My 70 (manual) fb idles high upon start...and then, after a few minutes...
> comes down.  usually at a light, i hear the adjust... it hasnt cut off yet,
> and i figured this was the auto choke working its magic.  am i wrong? is this
> normal? 

Assuming you're still FI, what you've noticed is the AAR (Auxiliary Air 
Regulator) in action. The AAR is a thermostatic automatic throttle, that keeps 
the idle speed just a little high until the engine is warmed up. Ideally, it 
would add just enough extra fuel/air to keep the rpm constant, in spite of the 
extra drag due to cold oil, but I suspect Bosch designed it to work just a bit 
on the high side.

Once the engine is fully warmed up, the AAR is fully closed, so it no longer 
has any effect.

Daniel's Type 34 is an almost one of a kind carbed AT Ghia, however, so this 
does not apply to him.  

-- 
Jim Adney
jadney@vwtype3.org
Madison, WI USA

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
List info at http://www.vwtype3.org/list | mailto:gregm@vwtype3.org
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~