Megasquirt II IAC setups for Dodge

[Turbo2.2Coupe]

I was wondering if anyone with MS-II knows how many steps a Dodge IAC has? When setting-up my MS-II I put in generic numbers to get it running. I bench tested several IAC motors but got inconsistant results, some motors went on forever but hardly seemed to move at all, other motors moved way faster than the rest, others would retract but not extend. As far as I can tell these IAC's are alternating motors. Has anyone ran into problems with MS-II IAC setups ? Thankyou, John.

[xrattiracer]

the dodge iac is a stepper motor, proper wire connections are a must.
I dont know how many steps to actually make one open all the way, but the dodge computers never open them more than 256 steps.

[mopar3.0]

all the ms guys here are not even using any kind of idle control

[87turbodance]

A two wire PWM valve would easier use to IMO.

[Shadow24V]

usually its 255 (256 numbers, but including 0) and i am running the mitso IAC stepper motor for now, but i may ditch it and go without the IAC

[87turbodance]

Quote:

Originally Posted by Shadow24V usually its 255 (256 numbers, but including 0) and i am running the mitso IAC stepper motor for now, but i may ditch it and go without the IAC

Grab a Ford PWM valve - it's just a controlled vacuum leak and it's easy to wire up.

[Turbo2.2Coupe]

Good info everyone. I thought about just setting the idle by adjusting the throttlebody, I also have some bosch idle valves lying around. I was going to try the IAC first ,if it will be troublesome I will try one of the other methods.From testing 87-95 IAC's the wiring seems to be two outer leads for one coil and the two inners for the other coil. Do the PWM's respond well when you letup from high rpm/full throttle flogging ? I've never owned a car that had one.

[xrattiracer]

as a ford guy, i can say with a great degree of accuracy that the 2 wire pwm valves are complete junk, you would be better off without one. they are very inaacurate and difficult to control, and are very prone to getting stuck in place cuasing high or low idle.
for the stepper motors, not only do you have to get the coil pairs correct, but you have to get the polarity on each coil correct.

[Turbo2.2Coupe]

I messed around with four different Dodge IAC's on the bench and never got any consistant results in regards to polarity, steps, movement, etc,... . Seems like I should just go with setting the idle speed with the throttlebody and save the more complicated fiddlin' for later. When using mechanical idle control, everything in Megatune is set to zero for the IAC, correct?