TPS voltage and ECM interpretation

[Ludis Langens]

Dan Griffin wrote:
> 
> A somewhat related question:  How does the ECM know when to follow the
> idling commands?
> 
> As far as I can tell, when VSS is sending no pulses, (car sitting still )
> and gear selector sw. in park, possibly neutral... Hands must be off the
> gear selector...Fully warm eng. veh. must be stopped at least 30 sec. ...

GM likes to keep the idle a bit higher when the vehicle is moving.  The
idle will only be dropped down all the way when the vehicle stops moving
and stays stopped.  Further, an automatic will idle at different speeds
in drive vs. neutral.

-- 
Ludis Langens                               ludis (at) cruzers (dot) com
Mac, Fiero, & engine controller goodies:  http://www.cruzers.com/~ludis/
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