24 Hybrid rough idle in neutral only

[Junglejim]

Nearing 40000km. Backed out of garage and slipped into neutral while waiting for garage to close. ICE kicked in & engine began to fluctuate, nearly stalling at one point, so I flipped it to Park = smooth idle. Forward/reverse whilst holding brake = smooth idle. Put in neutral again = same rough idle. Temps are near freezing outdoors, around 10 degrees warmer in garage. Anyone else experience this problem & determine a diagnosis/fix?

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[HeyBales]

It's a thing.

The unwarmed up tranny Generator Motor has to match the ICE RPM by ratio to prevent movement - since there is no true Neutral that disconnects the ICE from the wheels.
It appears it likes warmth better than cold.
So not sure if it's the ICE RPM varying enough the GM is trying to hit the correct RPM, or the GM just isn't warmed up yet.

ETA - Actually need to find the other video showing the noise, this is different noise when it's warm out. Same aspect of ICE RPM and GM RPM, except this is just showing regen going on.

 

[Mavster Mechanic]

Nearing 40000km. Backed out of garage and slipped into neutral while waiting for garage to close. ICE kicked in & engine began to fluctuate, nearly stalling at one point, so I flipped it to Park = smooth idle. Forward/reverse whilst holding brake = smooth idle. Put in neutral again = same rough idle. Temps are near freezing outdoors, around 10 degrees warmer in garage. Anyone else experience this problem & determine a diagnosis/fix?

It does that when cold.
It is not unusual.
Nothing is broken.
Nothing to worry about.

Just don't put it into N on a cold engine on a cold day if it bothers you. The times you need to are few and far between.

It's also due to the cold engine being in "open loop". Open loop means it is guessing what the air/fuel ratio should be without actually using data feedback from the emissions sensors because the emissions sensors are too cold to be useful too and in N the generator can't help smooth out the engine.

 

[Mavster Mechanic]

"N" is a simulated neutral. As you know, there is no gear removed in N position.

N means "no power to traction motor or generator motor". Zero power. Zero electric torque. The generator freewheels. The traction motor, as always, does whatever the wheels do.

 

[Larrythelunatic]

You start out in ”P”.
When you say “N”, the back-up camera comes on, seemingly to actually be in “R”.
Then, when you say “D”, the noise changes, but the back-up camera stays on, which is an option in the owner programming.
You’re there, and I’m here. But it looks like you were never in “N”.
Help me to understand.

 

[HeyBales]

You start out in ”P”.
When you say “N”, the back-up camera comes on, seemingly to actually be in “R”.
Then, when you say “D”, the noise changes, but the back-up camera stays on, which is an option in the owner programming.
You’re there, and I’m here. But it looks like you were never in “N”.
Help me to understand.

Went slow past R and it registered so camera thrown on fast.
Faster than it used to prior to recall software upgrade.
You can hear the extra click over to N.

As I mentioned, that video was mainly showing the fact there is a difference is sound as the ICE is powering the GM for recharging the HVB.
Compared to N where it doesn't - that fact is shown onscreen eventually if you run in N long enough.

I know I did a video of the cold weather shake rattle & roll, haven't found it.

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