Idle control using Stepper Motor (M400)

[mr2andy]

Adam,
I had the max output table value at 200 but my min is 0. This explain why the valve only goes one direction and not the other. This is very helpful and I'll give it a shot this week.

I have read multiple places that stepper is not a recommended motor for idle control. Motec suggested a PWM motor for this application but most of the PWM motor I found online required a compatible Throttle body to mount it on. Do you know any PWM idle control valve that is screw on like this GM stepper motor I have?

[Scott@FP]

There are some Honda and Bosch PWM type IAV's with either small footprint flange or hose mount.

Don't give up yet just keep hitting F1 when you get stuck, but yes the PWM style idle valves are easier to get up and running, and take up fewer outputs, which can become a big benefit.

One of the drawbacks to the stepper setup is you can't 'see' exactly what its doing (step count/position doesn't track correctly vs. PWM which tracks position correctly), so it makes it much more difficult to get right.

[mr2andy]

By given the min value a -200 number, then valve is now working as expected. Now I just need to spend some time and dial in the right number for PID control.

I think eventually when I run out of the output, I'd convert it over to PWM valve, but until then, I guess I'll stick with the stepper motor.

Thanks guys..