RobHeinl

I drive an 87 944 n/a and am researching about our ICV- Bosch 0280140501. It has three terminals so I think it is unlikely that the ICV is Pulse Width Modulated. Does anyone here know if our ICV's are stepper motor controlled??

Thanks,
Rob

Spidey944

It's a stepper motor. Pulse with modulation is used for things like blower motor fans and such on modern day vehicles. Older cars like ours just use varying voltages to change speed of fans, etc.

RobHeinl

Thanks for your reply, Doug. It is not common to have PWM controlled IAC's but it is used on the occasion. Bosch makes a 2-pin PWM IAC along with others.

You are correct about our IAC (ICV according to Porsche). After doing further investigation I found this thread: http://www.rovernet.net/asp/megasquirt.asp

It has a simple schematic of our IAC and (for my purposes, very helpful) how one could use Megasquirt to gain control of the IAC.

Thanks!