Please note: If a “DBW delete” has been installed on a Toyota ETCS-i TB or the idle valve has been deleted from the engine, The engine has lost the ability to control idle well with air flow. Engine idle can no longer be controlled like OEM. You can only resort to [Ignition control] idle only and setting the min throttle plate position open enough to try to prevent stalling and cold starts and let Ignition Idle control retard the timing down to 0 deg or slightly negative to reduce idle RPM.

When making idle speed adjustment changes, this may target VE cells which have never been tuned. The VE values in those areas will need to be adjusted if the changes cause the engine to idle richer or lean during the adjustment. The VE table must be adjusted with the engine at its warmed up temp to correctly set VE. If any VE changes are made when the engine is cold, the VE values in those areas must be checked and re-tuned once the engine is fully warm.    

Table flow of idle DC: 

In the Graph Log when “idle control active” log parameter is “YES”, the EMU is using [idle ref table] DC% vs coolant temp and [idle target RPM].

- When [TPS] is above the % value under idle/Parameters/ [Idle Off if TPS over] and [idle control active] log channel is “NO”, the EMU switches to [idle RPM ref] DC% vs RPMs and no longer referencing [idle target RPM]. When [idle RPM ref] table value is higher than [idle valve DC] log channel value, this can cause an undesirable jump in RPMs when the throttle is pressed from idle.

EMU uses [idle RPM ref] idle valve DC% to smooth the transition of engine RPMs when transitioning in and out of [idle control active] based on [idle On if TPS below] TPS%, [idle Off if TPS over] TPS%, and [idle control max RPM] values. [idle RPM ref] should be equal or lower DC% as [idle ref table] vs [idle target] and should slope steeply to “0” at higher RPMs based on [idle control max RPM] value.

Note: Toyota 1JZ vs 2JZ: There are (2) different IACV stepper motor OEM part numbers. If the idle RPM is very high during first start, enable the [Reverse] option in the Idle Parameters to check if the RPMs drop to normal. If lowering the Idle/[Idle ref table] value increases RPMs and increasing the value lowers RPM, the [Reverse] option needs to be enabled.

Helpful option:
Prevent engine stalling when letting off throttle:
[Virtual Target]  enabled- Idle / “Idle ref table” duty cycle must be fully tuned at all RPM Target axis rows to function correctly. 
Feature helps prevent RPMs from falling below base “Idle Target RPM”. 

It works by adding additional RPM to the base [Idle Target] value in the Idle / “Idle Target RPM” base RPM table to temporarily stop at a higher RPM to smoothly decrease RPMs back to “Idle RPM Target” base RPM table value. 

[Virtual target max] RPM value to add to [Idle Target] log channel

[Virtual target ramp down rate] RPM per second value. How fast or slow RPMs drop down to base idle target.

Note: Calculated [Idle Target] log channel available in Graph log and Tune Display.

[Virtual Target] superseeds [Activation target increase] settings. 

[Activation target increase], [Activation DC increase], and [Activation duration] can be set to “0” or used if helpful with configuration. 

To adjust initial idle speed:
First, clean the throttle body and fix any vacuum leaks before making any adjustments. Oil build-up in the clearance area between the throttle body and the throttle plate will reduce air flow resulting in an idle speed lower than normal.   

It is best practice to save your project file and individually save each parameter window for the ability to reopen those settings in case any changes result in a less than desirable condition.

For manual cable throttle bodies:  Temporarily disable [Idle/Ignition Control], Idle [PID control], and [EGO Feedback] to reduce AFR oscillations (if active). Zero out idle [DC VE Correction], [DC error corr.] and any other idle correction tables. 
[Afterstart DC scl.] table should be “100%” in all cells.
- Loosen the jam nut of the idle adjustment screw on the throttle body.
Note: Jam nuts are needed to prevent the idle screw from vibrating out and have a tendency to vibrate off and fall into unwanted places when left loose. It is highly suggested to snug up the jam nut before walking away from the engine bay.   

Initially set all cells in [Idle/Idle Target] table to "1000" RPM.

(If the engine runs when cold, skip and move on to When the engine is warmed to temp below.)  

-When engine is cold and idle RPMs are low:

Adjust the throttle body idle screw to increase RPMs to at least 1,000 RPM so the engine can stay running. You may need to readjust the idle screw to lower the idle RPM back down after the engine has reached warmup temp.

-When the engine is warmed to temp:

Adjust your idle screw on the cable throttle body to increase or decrease the idle RPM to around 1000 RPM. Lowering the duty cycle in the [Idle Ref table] will allow you to find the minimum duty cycle that will affect engine RPM.

A decent start on idle control can be obtained by initially setting [Idle Target RPM] to 1000 RPM (at the current warmed temperature of 175F to 190F degrees), lowering the duty cycle to 20%, and adjusting the idle screw to match an [Idle Target RPM] value of 1000 RPMs can reduce stalling while coming to a stop.  

For DBW throttle bodies: When engine is warm, configure [Idle target RPM] to desired idle RPM and follow the steps below. 

-To calibrate the idle valve or DBW to match your [Idle/Idle Target] from cold to warm coolant temps, [Idle/Idle ref table] is "idle duty cycle adjustment vs coolant temp".  

When connected to the EMU, a white vertical indicator line in the table shows you the current cell value being used per CLT Temp.
When you want to lower or raise idle speed, set your required RPM in the [Idle/Idle Target] table, then adjust the DC% values in the [Idle/Idle ref table] to match your [Idle/Idle Target].

Once idle speed has been tuned correctly and controllable, you can re-enable other idle features one at a time if they are needed.

-For DBW (Drive By Wire) or Toyota ETCS-i electronic throttle body (EMU Black):

Verify the EMU Black firmware is flashed to FW 2.113 and the “DBW Calibration Tool” has been previously run under Tools at the top of the EMU Black Client. If not, run the DBW Calibration Tool before first for the best results.

Then follow the step above “-To calibrate the idle valve to match your [Idle/Idle Target]”.

- Idle Duty Cycle when transitioning out of idle control:

Idle/[Idle RPM ref] table tells the EMU what DC% should be when transitioning when pressing the throttle and [idle control active] in the graph log changes to “NO”. This is based on DC% vs RPM. 
If the [idle ref table] values are very low (single digits) and the idle RPMs can not be reduced with enough control, DBW / Parameters / [Idle range] can be decreased. [Idle range] in the DBW parameters window is a multiplier for the idle ref table.
Note: Click the blue “?” in the Idle ref table window to see idle DC calculation information DC ref * Idle range when DBW idle is used.