Strange Idle Target RPM Increase

V3 BETA TESTS
1

First I indicated this here Idle and warm up tuning

But as this is something to take a closer look by itself I decided for a separate post.

As I’m working on air-cooled engines, I expect the higher CLT temps and things related to them are not that much tested as with water cooled engines.

The thing is I have Idle Target RPM table defined as below:
Zrzut ekranu 2024-08-11 o 13.12.45

And by some reason this target gets increased to almost 1400 RPM in the range of c.a 126+ deg Celsius by a reason not understand by me.

This is something that is occurring every time I start the engine and bring it to the warmed up state (c.a. 150 deg Celsius). When I stop the engine and cool it to c.a. 126 Celsius, the target drops to the value defined in the table.

Zrzut ekranu 2024-08-11 o 13.10.18
Zrzut ekranu 2024-08-11 o 13.10.181177×764 65.9 KB

What is interesting it seems when I stop the engine, the target still gets increased with the engine cooling gradually (which kinda makes sense without this “addon of ~300 RPM”, as I want more RPM with cooler engine to get a drop to “normal” around 126 deg).

Attaching log with few start ups / warm ups / cool downs.
20240811_1321-Idle-Target-RPM-Increase.emublog3 (2.3 MB)

What I am missing?

2

it looks like a type overflow error i code

3

So I think I found a clue, but not a solution I think.
By some reason when I set up the after start RPM increase as follows

Zrzut ekranu 2024-08-11 o 13.43.45

Even if the CLT temps are high it takes the 300 value from the lower left corner and adds it to the Idle RPM Target. Why?

And it keeps it like that even after power cycle. When I zero that table, then obviously it’s not added to the Idle Target RPM.

4

Indeed this table is a problem. For the next version this table will be modified to allow enter higher values in Y axis bins.

There is no workaround in this version. You need to keep this table 0.

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