[Shalmaneser]

See this very quick video:

https://youtu.be/SB7iU1RDZcg

Getting some very strange behaviour! Anyone seen this before? Have tweaked frequency from 60/100/150/200Hz and while the ICV responds properly I get these uncommanded movements the whole time??

ICV is one of these, used in some M44 motors I think?

https://www.bimmerworld.com/BMW-Parts/B ... 35846.html

[PSIG]

Have you tested the pins for expected "3-pin" motor resistances — or 'scoped the OEM signals?

[Shalmaneser]

It seems to work fine as a 3 pin ICV - opening changes as I adjust duty cycle, buzzing frequency changes depending on Hz, it's just this snapping issue! Will try and get a scope on it.

[PSIG]

Ah, OK. Post your 'scope captures.

[JHolland]

Are you running open-loop or closed loop?

[Shalmaneser]

Are you running open-loop or closed loop?

I've tried both but no change.

[PSIG]

Ah, OK. Post your 'scope captures.

And a current copy of your tune and relative log file while you're at it.

[Shalmaneser]

Some scope images attached, hope they mean something to someone!

As a test I bought a cheap unbranded ICV of the same design to make sure my original ICV is still good - saw the same behaviour, flicking to full open for a split second. Couldn't see anything on the scope aligning with these movements. I do see random spikes on the waveform? Could these be it?

No log as I've not been able to get it started yet!!

tune attached.

[JHolland]

The spikes aren't anything to be concerned about, that is just the result of switching a coil. What is the resistance of the ICV? Try putting a small value resistor in series with the coil and measuring the voltage across that, that will show us what the current waveform looks like.

[LPG2CV]

To me, the fuel looks to be twice what it should be.

You should set the required fule when sequential is selected. Then when changing to paired, the ms value, will become half of the rf value. It's the ms value that is used when calculating fuel.