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software issue? closed loop idle e-throttle

Tommy Luhr

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Hi! i'm tuning a Mercedes M120.980. A 6liter  V12 with a Link Thunder.

Dual Bmw s54 throttle servos and 12 Mikuni throttlebodies.


Everything runs great and i'm in to tuning drivability when i come to a problem.


If i choose to use Closed loop idle control via E-throttle i get a weird problem. 

full throttle when engine stalled is 100% tp Main.

Full throttle with engine running is not full throttle on tp Main.


This is because the "icl cl trim" is doing a -5.1% (this is different) then there will only be 94.9% on the tp-main.


I can't se why closed loop idle is affecting top end throttle.

i submit a log file  thats prove my conclusion.

Even submit the tune.

Have i figured out a software issue or is it my fault?

On the actual tune i'm running open loop idle and ignition idle. that works about okay.

There are not problem with that setup!


M120 443hp 95oct gas.pclr

Log 2017-03-22 9;00;52 pm.llg

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I think it might be a slightly unique case where you have a negative idle trim. (it should not be doing it but think you might be able to work around the issue)

Looking at your throttle target map you have a number of 0 targets but then jump to an 18% target at 3% throttle.

See if you can make the car idle ok jus ton the main throttle table.

Set your idle control to open loop sol/stepper. This will then disable the idle control totally.

Then work on you target table to get a good low idle at operating temp.

This should then allow you bring in idle control and only run positive corrections.   


Edited by Simon
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My throttle target map is a mess right now. Just playing around with it.

With open loop E-throttle idle and ignition idle set to on, the rpm is pretty solid.

But i want to use the closed loop function. 

It is a complex throttle setup with links from acctuators to the throttles. This can be why the dc % on the motors appears weird?

Maybe it is a pid tuning thing?


But the most important of all, is the Closed loop idle doing it wrong? 

Like  Simon says "it should not be doing it but think you might be able to work around the issue"

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