Just picked up a MegaSquirt 1 V3.0 and found out it can't natively drive a 4 - 6 wire Stepper IAC Motor. So I'm wondering if there's an aftermarket PWM valve that will fit in the GM TBI spot for the IAC Stepper motor.

(If anyone has any experience with MegaSquirt 1 V3.0 please let me know if there's a modification available to drive a Stepper IAC Motor.)

Is there anything online in terms of PWM replacements that fit into the GM TBI thread for the Stepper Motor?

 

I am digging this up because I am looking for the same answer. FluffyK, did you ever get a PWM valve to work? I have seen external ones piped in, but I would something I could fit to the throttle body.

 

Ditch the Megalasquat 1 - it's a dinosaur that should be left in the archaeological site you found it in. Get something that can actually drive stepper idle motors, etc. Our LINK products can easily handle this. There are other products that can also.

GD

 

Yeah I found the answer here. it's a page on how to make a stand-alone manually adjustable idle speed circuit using a GM type IAC valve (4 wire stepper motor) that's found in our cars. A video is included demonstrating how it works. The site includes a circuit diagram and a list of parts needed for the build.

Now, I did buy all the parts and attempted to build the circuit at home. I'm no electrician so I haven't gotten mine to work (might get someone online to build it for me).

In response to all those in this thread who discourage use of the MegaSquirt-I, I have had no problems with the operation of the product. I have saved a tremendous amount of money having bought the engine controller second-hand. It was pre-built and took minimal solder work to set it up for my application. While, yes I would recommend anyone to buy the Megasquirt-II logic board rather than the original Megasquirt-I in order to have the additional options, it is nevertheless possible to run a TBI small-block chevy with a Megasquirt-I, and some creative ingenuity.