Idle Control
The Idle Control function allows your Elite ECU to control the engine idle speed. There are multiple ways this is achieved with either Drive-By-Wire (DBW) control, a Bypass Air Control (BAC) solenoid with either two or 3 wire types, or via a Stepper Motor system. The purpose is to allow a controlled amount of additional air to enter the engine to increase or decrease engine torque, which in turn will raise or lower the engine speed.
Wiring Tab
Options
Control Method
Select the type of control method used for idle control.
DBW
The DBW Throttle is to be used for idle control. Only select this if a DBW Throttle has been correct configured. The DBW Throttle will be opened and closed by the Elite to control the amount of additional air.
BAC Two Wire
A two wire solenoid is being used for Idle Control. This will use a varying duty cycle signal, similar to a fuel injector, to control the amount of additional air. Typically zero duty will fully close the valve, and full duty will fully open the valve.
BAC Three Wire
A three wire solenoid is being used for Idle Control. This will actually use two solenoids that share a common 12V+ power supply. Typically one solenoid is used to increase air flow from a middle position, and the other solenoid is used to decrease air flow from a middle position. Without any connection these solenoids will typically flow half of the available amount of air.
Ignition Only
Suitable for vehicles without a Drive By Wire throttle or Idle Air Control Valve.
Stepper Motor (Absolute)
A four wire stepper motor is to be used for Idle Control. In Absolute mode the Idle Control will calibrate the stepper motor to find its position by winding in the motor by the amount set in the Full Range, and then winding out to the Base Duty amount. For a Stepper Motor the Duty refers to a percentage amount of the Range. The ECU will then control the Stepper Motor by following commanded values in the Idle Control base tables.
Stepper Motor (Relative)
A four wire stepper motor is to be used for Idle Control. In Relative mode the Idle Control will simply open or close the idle valve depending on whether it is above or below the target, and not follow any Idle Control base tables. Long Term control is not available with this Signal Type.
Connections
Main Output
DBW
This will automatically select the DBW unit if DBW has already been configured.
BAC Two Wire
Select the wire to be used to supply the duty signal to the BAC solenoid.
BAC Three Wire
Select the two wires to be used to supply the duty signals to the BAC solenoids. If the connection is not known and the two outputs are backwards, the idle control will simply operate in the wrong direction.
Stepper Motor (Absolute)
Sets the four dedicated Elite Stepper wires that are to be connected.
Stepper Motor (Relative)
Sets the four dedicated Elite Stepper wires that are to be connected.
Long Term Trim Tab
Long Term Trim for the Idle Control allows the Elite ECU to learn the required Duty that is needed to keep the engine RPM on target.
Enabled Long Term Trim
Enables the Long Term Trim control of the Idle Control. (Default = Enabled)
Reset
Resets all Long Term correction tables back to zero for all values.
Apply To Base Table
Applies any Long Term corrections to the Base table, and after applying these changes it will reset to zero for all values.
Idle Control Tab
Mode
Choose from Open or Closed Loop mode
Closed Loop
Allows the ECU to make adjustments to the idle output to keep the idle on Target.
Open Loop
Requires the tuner to adjust the idle output manually and the ECU will not make any adjustments from this.
BAC Type
Only available when BAC Three Wire is selected as the Signal Type. This configures the type of solenoid control that is to be used.
Uni-Directional
Both outputs will have the same duty. i.e. When the Main is 25% the Slave is 25%.
Complementary
When one output wire is increasing duty the other will be inverted and decreasing duty. i.e. When the Main is 25% the Slave is 75%.
Bi Directional
One solenoid controls 0-50% of the valve opening, the other controls 50% to 100% of the valve opening. The solenoid itself defaults to 50% open when no connection at all is present.
Frequency
Available when BAC Two Wire or BAC Three Wire is selected as the Signal Type. Sets the frequency at which the solenoid is to be pulsed. (Default = 300)
DBW Max Position
Available only when DBW is selected as the Signal Type. This sets the amount of throttle percentage that will be used when 100% Duty is commanded by the Idle Control. (Default = 10)
Output Max
The maximum amount of Duty Cycle that can be output by the Idle Control. (Default = 100)
Stall Offset
When RPM falls this amount below the Target RPM the idle output will be set to 100% to help save an engine from stalling. When RPM is above this normal operation will resume. (Default = 400)
Close Idle Valve On Boost
When enabled will set the Duty Cycle to 0% when there is positive boost pressure. Used when an idle control valve is not connected back into the pressure feed before the throttle body. i.e. it would cause a boost leak if the valve is not closed. (Default = Disabled)
PID Scaler
Allows for quick changes to the Proportional, Integral, and Derivative tables for testing purposes. A setting of 100% gives normal PID control. (Default = 100)
RPM Rate Lower Limit
Closed Loop control will only be active when the RPM is falling at a rate less than this amount. This setting is to prevent the idle control from making adjustments to try and reach the Target when the Idle is not yet stable by not operating the Proportional and Integral components. Setting this closer to zero will cause the controller to wait for a steadier RPM before starting the controller. Setting this further from zero will start the controller earlier. (Default = -300)
RPM Rate Upper Limit
Closed Loop control will only be active when the RPM is rising at the rate less than this amount. This setting is to prevent the idle control from making adjustments to try and reach the Target when the Idle is not yet stable by not operating the Proportional and Integral components. Setting this closer to zero will cause the controller to wait for a steadier RPM before starting the controller. Setting this further from zero will start the controller earlier. (Default = 300)
Decel Fuel Cut Restore
Decel Cut will not be active when the RPM is lower than this amount above the idle Target RPM, no matter what values are used in the Decel Cut Min RPM table. This is to ensure a Decel Cut RPM value cannot be set lower than the idle Target RPM. (Default = 200)
Eg. If the Target RPM is 800 and the Decel Fuel Cut Restore value is 200, then the 1000RPM will be the minimum RPM that can be commanded by the Decel Cut system.
Max Vehicle Speed
Active only when a Vehicle Speed Sensor is enabled. Sets the vehicle speed that the vehicle must be below before closed loop control of idle can commence. This is to let the Elite ECU know that the engine is at idle and is not being driven, and prevents possible stalling on long and slow deceleration. Although not required, it is highly recommended that a vehicle speed sensor is used when Idle Control is active. (Default = 10km/h)
Decel Offset
Sets the amount of extra duty to be added to the Base Duty when the throttle has been closed. This is used to help to catch the engine when the RPM is falling to prevent RPM dropping below the Target RPM. When normal idle conditions are met, this amount will decay back to normal over a period of time set in the Decel Offset Decay Time. (Default = 10)
Decel Offset Decay Time
The amount of time for the Decel Offset will decay back to normal operation. (Default = 2.50)
Stepper Motor Calibration
Selects the method in which the stepper motor will calibrate
Normal Calibration
Fully closes the stepper motor during calibration. If the engine is started while the stepper motor is still calibrating, the engine will initially idle low.
Reverse Calibration
Fully opens the stepper motor during calibration. If the engine is started while the stepper motor is still calibrating, the engine will initially idle high.
Throttle Follower (Dashpot) Enable
The Throttle Follower smooths the transition from open throttle to closed throttle. This is done by increasing the idle output based on the amount of rpm and load the engine is using and decaying it away as the throttle is closed.
Ticking this box enables the Throttle Follower. This activates the "Throttle Follower Target" and "Throttle Follower Decay" Tables in the ECU Navigator.
Idle Up Tab
Allows an external input to be configured such that the idle control can be increased for any condition.
Air Conditioning
Air Con Idle Base Offset
Active only when the Air Conditioner Control function has been enabled. The Base Duty will be increased by this amount of duty cycle when the Air Conditioner Output is active. (Default = 5)
Air Con Idle RPM Offset
Active only when the Air Conditioner Control function has been enabled. The Target RPM will be increased by this amount of RPM when the Air Conditioner Output is active. (Default = 50)
Power Steering
Base Duty Cycle Offset
Active only when the Power Steering Switch Input function has been enabled. The Base Duty will be increased by this percentage of duty cycle when the Power Steering Switch is active. (Default = 5)
RPM Offset
Active only when the Power Steering Switch Input function has been enabled. The Target RPM will be increased by this amount of RPM when the Power Steering Switch is active. (Default = 50)
Electrical Load
Base Duty Cycle Offset
Active only when the Electrical Load Switch Input function has been enabled. The Base Duty will be increased by this percentage of duty cycle when the Electrical Load is active and signalling that there is a load significant enough to affect Idle (e.g. headlights). (Default = 5)
RPM Offset
Active only when the Electrical Load Switch Input function has been enabled. The Target RPM will be increased by this amount of RPM when the Electrical Load is active and signalling that there is a load significant enough to affect Idle (e.g. headlights). (Default = 50)
Air Pump
Idle Delay
The delay time used to allow idle to stabilise, before the air pump puts a load on the engine.
Generic Idle Up 1-4
The input must be configured as a Generic Sensor.
Enable
Enabled or Disables the Generic Idle Up.
Input
Select the Generic Sensor to be used for Idle Up.
Base Offset
The amount of duty to be added to the Base Duty while the Generic Idle Up is active.
Related Tables
Target RPM
The amount of engine speed that is to be targeted by the Idle Control. Up to 3D mapping is available.
Post Start Target Offset
The amount of additional RPM to be added to the Target RPM on initial engine start up. This is typically configured to decay away to zero over engine running time. Up to 2D mapping is available.
Min Output
The minimum amount of duty that the system will allow. Even if tables command lower this amount still will be the lower limit.
Base
The amount of duty required for the RPM to match the Target RPM. This will need to be manually adjusted if the Long Term Trim is not enabled. Up to 3D mapping is available.
Post Start Base Offset
This will add an amount of duty to the Base Duty after the engine has been started. This is to assist Idle Control in reaching the additional RPM added by the Post Start Target Offset and is normally mapped to return to zero after a certain amount of time. Up to 2D mapping is available.
Proportional, Integral, and Derivative Gain
This allows mapping of the PID system, which controls the responsiveness of the Idle Control system. In simple terms the Proportional controls how fast the system will respond relative to how far it is from the target, or high reactive the system is. The Integral is how aggressive the Proportional changes are. Derivative is used to slow down overshooting the target if the Proportional has been aggressively tuned. Up to 3D mapping is available for all PID tables.
Long Term Trim Gain
Controls the rate at which the Long Term control can make corrections to the Long Term Trim table. 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.
Long Term Trim
Shows the amount of correction the Long Term Trim is making. This table is user definable for axis values, however the axis channels are fixed to be the same as are used for the Base Duty Cycle table. This table can be adjusted by the tuner simultaneously whilst the Long Term Control is making changes. Up to 3D mapping is available.
Ign Corr
An ignition correction that allows for ignition timing to be advanced or retarded when the RPM is above or below the Target RPM, and idle control is active. Typically the timing will be advanced when below the Target RPM to add engine torque, and retarded above the Target RPM to reduce engine torque. This is helpful in maintaining a stable idle on the Target RPM due to it being faster responding in changing engine than an idle valve. Up to 3D mapping is available.
Throttle Follower Target
Axis selection and changing values
This table is intended to be used with RPM set as the first/x (left to right) axis and Pedal Position Source as the second/y (bottom to top) axis, though these 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
Only available when the Throttle Follower is enabled. This is the target for the Throttle Follower Idle Offset. This table is always active whenever the Throttle Follower is enabled. For this reason, when pedal position is 0 around idle conditions, table values must be 0 (at higher RPM and 0 values for pedal position, the target can be positive, however must be low as to ensure correct return to idle). The Throttle Follower Target is typically mapped to have a larger amount when either rpm or load is increased - these sites must be tuned by feel. This can be done on a dynamometer, however road testing is suggested to ensure correct feel.
For a vehicle equipped with a DBW Throttle, the Throttle Follower Target % is a percentage of the DBW Max Position setting (found in the Idle Control tab of the Idle Control function). Note that if Idle Control is demanding close to the max position, the Throttle Follower Target offset will not allow the throttle position to exceed the set Max Throttle Position.
Note that the decay time is used whenever the value is decreasing; typically when closing throttle.
Throttle Follower Decay
Only available when the Throttle Follower is enabled. This controls the amount of time to decay the Throttle Follower Target away. This decay is started when the throttle is moving in the closed direction. Traces below show this in action.
DBW Vehicles
The white circle shows where the Throttle Follower decay is active. The throttle follower output and target are the same as the throttle is increased, however when the throttle is closing, the decay table is active, causing the Throttle Follower output to decay over a set time.
This in turn slows the rate of closing of the throttle (for DBW vehicles only, as the idle control is output by the DBW throttle). This is seen where the throttle position (green trace) decays slowly in comparison to the accelerator pedal position (yellow trace). This is shown more clearly in the trace below.
Non-DBW Vehicles
The white circle shows where the Throttle Follower decay is active. The throttle follower output and target are the same as the throttle is increased, however when the throttle is closing, the decay table is active, causing the Throttle Follower output to decay over a set time.
This in turn slowly returns the idle control offset back to normal idle conditions, as seen where the Idle Control Output (red trace) decays slowly in comparison to the throttle position (blue trace). The trace below shows the Throttle Follower output decay compared to the throttle position.
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