[Marvin2Shoes]

I would test independently first, to confirm operation. At least connecting for homing independently, so it has full and correct authority with the throttle stops for now.

I thank you again, I have my work set out for the day then

[Marvin2Shoes]

I would test independently first, to confirm operation. At least connecting for homing independently, so it has full and correct authority with the throttle stops for now.

I plugged the stepper driver board into the NO2C after viewing the image using the link below... to ascertain which way the board plugs into the NO2C.
I then set up Stepper Idle control on Tuner Studio to enable use of the stepper motor.
I turned on the NO2C and nothing happened so I started the engine, still with no connection to steppers. Engine still ran.
I then tested the output of the stepper A1-A2 and got 0.5V.
I ran the NO2C through a few power ons testing the output of the stepper driver with the same result - No drive to the stepper motor connections A1 & A2.
I then swapped out the driver board for a second board on the off-chance the first was faulty.
On power-up I noticed the smoke come out of this one so no doubt the first has suffered the same fate.
I then thought I'd look at further pictures of the NO2C online as I would walk ten miles to not have to look at the schematic on github to check it against the physical board.
it seems the GND connection on the stepper board must be connected to the pin at the edge of the NO2C board. I can't see any designation information anywhere and there is very little printed on the NO2C board except GND.
Can anyone tell me if the driver board in picture attached is correctly oriented?
LINK TO PICTURE: https://i.ytimg.com/vi/2ty8RvaTWjM/maxresdefault.jpg

[LAV1000]

maybe this one helps:
https://speeduino.com/wiki/index.php/Idle

[Marvin2Shoes]

maybe this one helps:
https://speeduino.com/wiki/index.php/Idle

That's silly... I did read that and adjusted the pot according to the text but never noticed the picture was the stepper board.... probably because it has the heat sink on it. They say not to attach it.
Well this is worrying.... there is no apparent reason for the board letting its smoke out.
I'll put the last working stepper board in my other no2c and see how that goes.

[apollard]

I had several stepper drivers fail. Most smoked immediately, some ran a mknth or two. I gave up on them and use timing to center the idle. IME, 5he boards were just crap, but they also cost very little delivered via China post

[Marvin2Shoes]

I had several stepper drivers fail. Most smoked immediately, some ran a mknth or two. I gave up on them and use timing to center the idle. IME, 5he boards were just crap, but they also cost very little delivered via China post

Well that's good to know... I could have been 500kms from anywhere when a stepper died... Not happy with that sort of hit & miss tech.
Is there a doc on how to set up the timing method... Are we talking a relay supplying voltage for a set time?

[LPG2CV]

@apollard is talking about a timing trough.

In the spark table, you add advance to the cells on the left, in the rpm range where the engine idles.

The idea is, as the rpm drops, it drops into cells with more advance. More advance gives more torque, and the engine doesn't stall.

[Marvin2Shoes]

@apollard is talking about a timing trough.
In the spark table, you add advance to the cells on the left, in the rpm range where the engine idles.

Ah... Ok that makes more sense. I'm wondering if I should remove the idle steppers and bolt covers over the holes left in the throttle bodies?

[LPG2CV]

Be cautious of any seals you may break, but perhaps you can remove one and see if it's physically possible to wind the pintle.

Be sure you can seal them again, so as not to allow false air, or you will be worse off than you are now.

[apollard]

Yes, a timing trough. I left the stepper since it was sealed and zero effort.

There is now an option in software to add/subtract timing to achieve idle. It's under Starting/Idle _ "Timing Advance Settings". I haven't used it since my idle is stable. But I'm running a 7.4L VB with lots of inertia, yours may benefit from the extra functions there. However, don't start on any ot the extra features until you have a good warm idle setup - then add features one at a time.