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Navigation: MTune Settings > Fuel

Fuel Adaptation

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Fuel Adaptation records lambda correction applied to a permanent trim table to compensate for long term changes to the main fuel table.

The fuel adaptation system uses target and range values from the Lambda control system.


Note: The adaptation table is saved in the ECU, and is stored even after a reboot, and it used by the ECU to compensate fuel, when active, see the RealTime Data value long term trim %.



Fuel adaptation


fuel adaptation

Specifies whether to use the built-in fuel adaptation system.

Note: Make sure your Lambda control targets and range values are correctly setup, and your Lambda target table.


table edge behavior

How the edges of the below fuel adaptation table should be threatened.

Update and apply edge value if outside table (recommended).

apply edge value if outside table.

no correction of outside table.


adaptation start CLT

The coolant temperature above which the system is modifying the trim table.



Fuel adaptation rate


adaptation rate

Specifies the speed of the correction, it is advice able to use a small percent allowed correction.

This should be slow at low load conditions where the engine spends most of the time, and faster at high loads where the engine spends less time.



Fuel adaptation table


adaptation trim table (updated by the ECu)

The fuel trim table determined by the ECU. This table is limited to 6x6 cells to get frequent updates to each cell. Distribute the cells so that they are close together where the engine spends most of the time (low load).

This tables size and axes ranges can be different from the Main VE table, trims values will be interpolated and boundary values will be used outside the trim tables range, depending on the table edge behavior setting.

Note: Do not manually modify this table (you can, but it is not intended for it)




Note: the fuel adaptation system is not intended to be used as an autotune system, it is meant to be used as a "long term trim" solution after the engine has been tuned by a professional.



1. Enable the fuel adaptation and enter a start CLT temperature, preferable when the engine is in normal temperature. Populate the adaption rate table to suit your need (start with LOW values here, below 1% is the recommended start values).

Not: DO NOT PUT to high values here, start slowly with low values!



2. Drive around and let the MaxxECU populate this adaptation table. It is advise able to manually review this table to check for large changes, which indicates a poorly tuned engine and/or some hardware issue.




3. Press the Apply correction to VE-table to apply the current fuel adaptation to the main VE table.

Note: After fuel adaptation applied to the main VE table, the fuel adaptation table will be automatically reset.