IAC

[dzorde at aesprodata.com.au]

     I'm using a Wolf 3D system which doesn't allow for control of the 
     standard IAC, thus I was thinking of either using:
     
     1. the old style solenoid switch that opens the throttle a bit when 
     power is applied.  Requires the original IAC mounting hole to be 
     blocked off.
     
     2. a temperature sensing bi-metal type air by-pass valve as used on 
     many Nissans.  Requires blocking of the original IAC mounting hole 
     also.
     
     3. Nothing at all.
     
     Dan        dzorde at aesprodata.com.au


______________________________ Reply Separator _________________________________
Subject: Re: IAC
Author:  diy_efi at coulomb.eng.ohio-state.edu at INTERNET
Date:    05/2/96 4:25 PM


You wrote: 
>
>
>     
>     On the subject of the GM IAC(idle air controller) for the TPI 
engines. 
>     Does anyone know of a replacement, working of sensing the 
temperature 
>     or similar, ie. some sort of bi-metal spring system.  The problem 
is 
>     that I need some sort of idle stabilisation on a TPI system but 
the 
>     ECU does not allow for control of the standard IAC.  
>     
>     Is it possible to leave the IAC off all together?  
>     
>     Any ideas will be appreciated.  Preferably the parts should be 
>     available of Australian cars, since US parts are to expensive 
over 
>     here.
>     
>     
>     Dan        dzorde at aesprodata.com.au 
>      
>
the iac is just a little stepping motor  gm bottoms it shut at start 
and then backs it off a a certain number of steps to control idle 
mixture air and also as a deceleration valve during throttle release 
closing. what sort of ecm are you using?
ford uses a solonoid thats pwm to do the same thing  but ive heard the 
gm stepper works better and smother as long as the valve lead screw is 
kept clean (i own a iac gm ).
maybe i could design a little gaget using a pic16 up.