O2 Control
O2 Control allows closed-loop (targeted) control of the fuel system via an O2 sensor that is used for AFR feedback to the Elite ECU. The Target Lambda table is used when a Wideband O2 Sensor is selected, and a Target Voltage table is used when a Narrowband O2 Sensor is selected. Corrections made by the O2 Control system are referred to as Short Term Fuel Trims (STFT) and are only temporary .i.e. they are not stored by the ECU. If the Long Term Control is enabled further corrections to the fuel system referred to as Long Term Fuel Trims (LTFT) are stored by the ECU and will not rest unless commanded to do so.
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O2 Control Tab
Bank 1
Select the type of sensor and the sensor number being used for O2 Control.
Bank 2
When a second engine bank has been configured, the type of sensor and sensor number on Bank 2 can be selected.
STFT Max Enrich
Sets the maximum positive (rich) correction that the Short Term Fuel Trim (STFT) will allow.
STFT Max Disenrich
Sets the maximum negative (lean) correction that the Short Term Fuel Trim (STFT) will allow.
Target Oscillation Amplitude
The desired amount oscillation around the target AFR or voltage. This function is used primarily for emissions purposes by improving exhaust catalytic converter efficiency. It is used more commonly for Narrowband O2 sensors to push the system into aforced oscillation. The value will be in AFR for wideband O2 sensors, or the amount of sensor voltage for Narrowband O2 sensors. (Default = 0, Typical Narrowband = 0.05V)
Warm Voltage
Active only with Narrowband O2 sensors. The sensor voltage that if exceeded will bypass the Initial Engine Running Time. i.e. if a warm engine is shut down and then quickly restarted, the narrowband sensor is already in a usable temperature state, and the Initial Engine Running Time can be bypassed to allow quicker entry into closed-loop control.
Initial Engine Running Time
The amount of time the engine has been running before closed-loop control will activate. This is to allow time for the O2 sensor to reach operating temperature. It will be bypassed if the warm voltage is exceeded or the CAN Widebands are reported as being ready to use. (Default = 30)
Min Coolant Temp
Below this Coolant Temperature value the O2 Control is disabled. (Default = 0)
Min RPM
Below this RPM value the O2 Control is disabled. i.e. above this RPM, O2 control is active. This is to prevent O2 Control from making fuel changes while the engine is cranking. (Default = 450)
Max RPM
Above this RPM value the O2 Control is disabled. This allows an upper RPM limit to be set for closed loop control and is more used for narrowband sensors or for the tuner's own preference.(Default = 4500)
Transient Throttle Rate Limit
The amount of transient throttle rate above which Closed Loop Control will be disabled. This allows the O2 Control to still operate with very small rates of throttle movement, but if this amount of movement rate is exceeded the closed loop control will pause.
Enable Max TPS
When enabled, allows a maximum TPS value above which O2 Control is disabled.
Enabled Max MAP
When enabled, allows a maximum MAP value above which O2 Control is disabled.
Long Term Fuel Trim Tab
The Long Term Fuel Trim is a function where the Elite ECU can learn the correct amount of fuel required over a period of time so that the Target and Actual measured AFR are equal. Sometimes this is referred to as Auto-Tune. Both Narrowband and Wideband O2 sensors can be used for Long Term O2 Control, however a Wideband O2 Sensor is preferred for broader Load and RPM usage, and for faster response. A Narrowband O2 Sensor should never be used for full throttle Long Term O2 Control. Long Term O2 Control can allow for fine correction of the Fuel Base table in areas that may not be obtainable during the tuning process, for engine wear over time, or for self-tuning for small modifications. Mapping is available up to 4D.
Enable Long Term Fuel Trim
Enables or Disables the Long Term Fuel Trim Function. When Enabled, new tables are available in the ECU Navigator. (Default = Disabled)
LTFT Max Enrich
Sets the maximum positive (rich) correction that the Long Term Fuel Trim (LTFT) will allow. (Default = 15)
LTFT Max Disenrich
Sets the maximum negative (lean) correction that the Long Term Fuel Trim (LTFT) will allow. (Default = 15)
Long Term Fuel Trim Rich Bias
Allows the Long Term to learn an amount richer than the Target to allow for a safe tune condition should the system revert to open loop control, perhaps due to sensor failure. The short term control would then correct back to the Target Lambda from this learned bias. To disable this function it should be set to "0". (Default = 3)
Long Term Fuel Trim Min Temperature
Sets the minimum coolant temperature before the Long Term control will activate. This is to prevent the long term table form learning values from a cold engine. (Default = 80)
Disable During Post Start Corr
When enabled, the Long Term control will be disabled when the Fuel Post Start Correction table is outputting anything other than 0%. This is sometimes required when the tuner does not wish to allow the Long Term control to function whilst a start-up enrichment is active. (Default = Disabled)
Disable During Coolant Corr
When enabled, the Long Term control will be disabled when the Fuel Coolant Correction table is outputting anything other than 0%. This is sometimes required when the tuner does not wish to allow the Long Term control to function whilst the engine is not at full operating temperature. (Default = Disabled)
Reset
Resets all Long Term correction tables back to zero for all values.
Apply to Base Table
Applies any Long Term corrections to the Fuel Base table, and after applying these changes it will reset to zero for all values. When a second engine bank is being used, the Long Term system will apply the difference between the two banks to the Fuel Base table, and any remaining differences will remain in the table. All values that were equal will reset to zero. This must be done in this way due to there being two Long Term correction tables, and only one Fuel Base table to apply to.
Setting up Tables
Delay
Under ECU Navigator>Lambda>O2 Control>select Delay
Axis selection and changing values
This table is intended to be used with RPM set as the first/x (left to right) axis, though both axes are user configurable to use any ECU channel. Changing the axis values can be accomplished by pressing F3 when the table is selected, then either editing an existing value or adding a new value. Note that if you edit an axis site value, the overall table values will be adjusted so that the shape of the table is unchanged.
Tuning
The amount of time after a particular function has caused the O2 Control to stop before it can be started again. It is used to give time for the exhaust coming out of the engine to reach the sensor. Sometimes referred to as Travel Time.
Proportional Gain
Under ECU Navigator>Lambda>O2 Control>select Proportional Gain
Axis selection and changing values
This table is intended to be used with TPS set as the first/x (left to right) axis, and RPM as the second/y (bottom to top) axis, though both axes are user configurable to use any ECU channel. Changing the axis values can be accomplished by pressing F3 when the table is selected, then either editing an existing value or adding a new value. Note that if you edit an axis site value, the overall table values will be adjusted so that the shape of the table is unchanged.
Tuning
Using layman's terms, the Proportional Gain adjusts how reactive the system is relative to how much error there is. Increasing this makes the Short Term react faster. Set too high will cause rapid oscillations in the AFR. Proportional should have low numbers (approximately 10 to 100) for Narrowband control, and higher numbers (100 to 300) for Wideband control.
Integral Gain
Under ECU Navigator>Lambda>O2 Control>select Integral Gain
Axis selection and changing values
This table is intended to be used with TPS set as the first/x (left to right) axis, and RPM as the second/y (bottom to top) axis, though both axes are user configurable to use any ECU channel. Changing the axis values can be accomplished by pressing F3 when the table is selected, then either editing an existing value or adding a new value. Note that if you edit an axis site value, the overall table values will be adjusted so that the shape of the table is unchanged.
Tuning
Using layman's terms, the Integral Gain adjusts how large of a step the Proportional makes. Increasing this makes the short term use larger steps when trying to reach the target and help push the system to reach the target when the error is small. Integral should also have similar low numbers (10 to 100) for Narrowband control, and higher numbers (200 to 500) for Wideband control.
Derivative Gain
Under ECU Navigator>Lambda>O2 Control>select Derivative Gain
Using layman's terms, the Derivative Gain adjusts how aggressive the Proportional is when it is approaching the Target. Increasing this can help prevent overshooting when the Proportional is set high but it can also prevent ever reaching the target. Derivative is typically zero for Narrowband control as overshooting the target is often desired, and will also be zero or very small numbers (0 to 10) for Wideband control and is used to slow down overshooting the target if the Proportional has been aggressively tuned.
Long Term Fuel Trim Gain
Under ECU Navigator>Lambda>O2 Control>select Long Term Fuel Trim Gain
Controls the rate at which the Long Term O2 Control can make corrections to the Long Term Fuel Trim tables. Larger numbers will learn faster but can cause oscillations, and smaller numbers will make corrections at a slower rate. Up to 3D mapping is available (Default = 30)
Bank Long Term Fuel Trim
Under ECU Navigator>Lambda>O2 Control>select Bank 1 Long Term Fuel Trim
Axis selection and changing values
This table is user definable for the axis values, however the axis channels are fixed to be the same as those used for the Fuel Base table. Any axis values that are changed for this table are also changed for Bank 2 if a second bank is active. This table can be adjusted by the tuner simultaneously whilst the Long Term Control is making changes. Up to 4D mapping is available.
Tuning
The amount of fuel percentage correction that the Elite ECU has learned for each given cell, or in other words, the amount of correction the Long Term O2 Control is making to Bank 1.
Bank 2 Long Term Fuel Trim
Under ECU Navigator>Lambda>O2 Control>select Bank 2 Long Term Fuel Trim
Axis selection and changing values
This table is not user definable for the axis values or channels, it instead will use the same values as for Bank 1. This table can be adjusted by the tuner simultaneously whilst the Long Term Control is making changes. Up to 4D mapping is available.
Tuning
The amount of fuel percentage correction that the Elite ECU has learned for each given cell, or in other words, the amount of correction the Long Term O2 Control is making to Bank 2.
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