[tech]: idle specs on a 2.0L 16v cis-e?

[jason@scirocco.org (16V Jason)]

At 04:10 PM 1/18/2002, Michael Abatzis wrote:

>The idle stabilizer valve will keep idle at the same value that the
>>1.8 was
>>(+-900rpm IIRC).  It might have a higher duty cycle (be open more often)
>
>but since the idle speed is set by adjusting the duty cycle, wouldn't you 
>need to set it to a different value? or will the system automatically 
>compensate? my thinking, lmk if this is basically correct: with stock 
>settings, airflow to the 2l is too low, so idle is low. computer senses 
>low idle speed, increases duty cycle. when i check the duty cycle at idle, 
>it is now higher than it would be on a 1.8. so if i try to set it back to 
>spec (~26' dwell iirc), i'm actually setting it too low for the 2.0.
>does this make any sense? i'm having a hard time putting my feeble 
>thoughts into words here...

Your thinking does make sense -- I think. :)
Unfortunately I don't have my Bosch manual in front of me -- but lemme ask 
everyone:  Is the idle speed adjusted by the duty cycle?  Or (if my 
understanding is correct), does the duty cycle just indicate whether the 
idle air bypass screw is adjusted properly?

If I'm right, and the computer knows idle speed, and changes duty cycle to 
keep it where it's supposed to be (but can only do it within certain limits 
and therefore you have to check the duty cycle to see if the screw is in 
the right range), then Michael's right... the duty cycle would be higher 
than it was in the 1.8... which would mean that the idle adjustment screw 
should technically be adjusted to bring the duty cycle back down.  However, 
if the car still idles perfectly, then the idle screw is set to a value 
that is still within the aux air bypass's ability to stabilize it and 
therefore it's not 100% necessary to adjust anything.

...or am i just nuts? :)

Jason