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Guide on Rate of Change % Closed Loop Tuning

Practical Reflash Tuning

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Hello guys,

Im having an issue trying to understand the rate of change in percentage for the closed loop tuning. What characteristics of the engine this option affects and how i can optimize it?.

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This adjusts how fast your closed loop responds to the current conditions. Let's say at 1000 RPM the Lambda Aim was 1.0, but it measured 0.95 -- it needs to remove 5% fuel, how fast does it make that change? Based on the screen shot, I would expect it to remove 5% in in 5/64 = 0.78 seconds. If you find your closed loop fueling oscillates at fixed engine conditions, then I would use a smaller number in the table at that engine speed. If it takes too long to respond, I would use a larger number.

I would expect the table to have small values at low RPMs, and larger values at higher RPMs, as there is less mass flow at lower RPMs and it takes longer for the Lambda sensor to respond, so you wouldn't want to make your changes too quickly. The faster the engine is turning, the quicker responding the lambda sensor will be and the faster you can make the changes.