Motec M1 -- Idle Control

Hi

Car:

2jz Non-VVTI 12 tooth,

OE Cam/Crank VR sensors ,

Denso 6731200 coil packs

DBW, Bosch (0 280 750 473.1.0)

FIC 1440 Injectors

Coolant Temp Sensor -- Bosch 0 280 130 026.1.0

Air Temp Sensor -- GM Delphi ,Default 35 Degrees

Goal: Get my car idling correctly

Observations

Injectors: FIC1000CC linerisation was used from the drop down , I have upload the MoTec Supplied FIC1440 table

Idle Throttle actuator Aim is set at 100% , suggested this should be set at 15%

Idle Activate Throttle Pedal Thresh is set at 4.0% , recommended value 0%

Idle Activate Throttle Pedal Hysteresis is set at 0.4% , recommended value 0.1%

I have done some webinars on Idle control ,

Questions

It is reiterated multiple times , All Idle Control Parameters are Default before starting!

What exactly does this mean ,

Parsing through the Idle menu and sub menus, setting all parameters as per MoTec M1 Help typical values ?

Mass Flow feed forward table -- how to I determine the default values here?

It is a Japanese engine , from my comprehension

Japanese engines – NBT Numbers 14 – 15 degrees

What firmware package are you using? The GPx packages don't have "Idle Throttle actuator Aim", they have "Idle Throttle Actuator Aim Max" which is the maximum throttle the Idle system will ever command (per the help, this is typically 10% to 15%. Everything about Idle Mass Flow will change if this value is modified. What you want is the throttle required to hold the engine speed about 1000 - 1500 RPM above your target hot idle speed. The description in the help describes it exactly -- is there something you don't understand about this.

I agree that Throttle Pedal Threshold should be 0% for DBW, values of around 2% usually are required for non DBW throttles.

I would review all the help, and set any values to the typical or recommended, unless you have reason not to (for example, you package is for an engine with a similar DBW setup that is running well).

Idle Mass Flow Feed Forward. Enable the axis for Idle Aim and Coolant Temp (changes in these values require a different Mass Flow Feed Forward amount). Make sure one of the Coolant Temp axis values is the same as your normal operating temp. Create Idle Aim axis values for nice round numbers (say 800, 1000, 1200) and go up to the Maximum achievable from Idle Aim Main + Idle Aim Ramp Down Limit + Idle Aim Compensation.

The general table shape is the value increase from lower Idle Aim RPMs to higher Idle Aim RPMs. The values will decrease as the Coolant Temp Increases. I would start with 40-60% at normal operating temp across the RPM range (interpolate that range). And maybe add 10% at the lowest coolant temp (and interpolate that range). Follow the trend for higher coolant temps.

To tune - follow the procedure in the help for Idle Mass Flow Feed Forward. Basically, set the Idle Aim Main table to just a single value (a row in the feed forward table), then populate the table with the resulting value of the channel "Idle Mass Flow" (which the result of the PID adjusting the throttle to achieve the ignition timing specified in "Idle Ignition Timing Limit Advance Target"). Then change the Idle Aim Main to another column and repeat. After a bit, you will have the shape of the table, and can adjust other values with a reasonable guess. You can confirm sometime when the coolant temp is low, and do a whole RPM column as the engine warms up. Repeat with a different RPM once the coolant is low again (usually the next day).

If your "Idle Mass Flow" does not adjust to achieve the target RPM, then try increasing the "Idle Mass Flow Proportional Gain" -- I find that is usually needed, especially when the Feed Forward table hasn't been tuned. Later you can decrease this and count on the Feed Forward and Integral to make more subtle/stable adjustments.

Hope that helps --