Subaru Accesstuner Tuning Guide Supplement
...
| Anchor | ||||
|---|---|---|---|---|
|
The following Subaru models are applicable to this document:
- 2014 - 2018 Subaru Forester XT
- 2015 - 2019 Subaru WRX
| Anchor | ||||
|---|---|---|---|---|
|
...
The following are steps to force the DIT ECU into full-time closed loop. Warning: This has not been extensively tested on our end and it is not clear if running full-time closed loop is optimal or not or if it results in accurate/responsive fuel corrections all the time After making these changes, verify that the ECU remains in closed loop at high load by testing on the car.
- In the "Fuel Tables" → "Closed Loop Target" table group:
- Tune the four "Closed Loop Fueling Target Base (Main)..." A,B,C,D tables and the "Closed Loop Fueling Target Base (Alternate)" table to reflect your desired full-time closed loop fuel targets.
- Set the "Closed Loop Fueling Target Final (Alternate)(Aggressive Start)(Primary OL Fuel Compare) Activation (Max. Coolant Temp)" table to -40 - this disables the "aggressive start" table alternate closed loop target from coming into play.
- Tune the four "Closed Loop Fueling Target Base (Main)..." A,B,C,D tables and the "Closed Loop Fueling Target Base (Alternate)" table to reflect your desired full-time closed loop fuel targets.
In the "Fuel Tables" → "Closed/Open Loop Transition..." → "Delay" table group:
Set the delay values in the "Closed to Open Loop Delays" table to 65535 across the entire table.
- In the "Fuel Tables" → "Closed/Open Loop Transition..." → "Delay Deactivation Thresholds" table group:
- Set all the "Load vs. Rpm Component" raw values (z-axis) of the following tables to zero:
- Closed Loop Delay Max. Load vs. RPM Component Determine (Alternate) - (15+ WRX/16+ FXT only)
- Closed Loop Delay Max. Load vs. RPM Component Determine (Primary Fuel Min. Activation Met)
- Closed Loop Delay Max. Load vs. RPM Component Determine (Primary Fuel Min. Activation NOT Met)
Make sure the "Closed Loop Delay Max. Load vs. RPM Component Threshold (Smoothing Factor 1)" and "...(Smoothing Factor 2)" tables are both set to 65535.
Set all the Engine Speed (RPM) value(s) in the "Closed Loop Delay Max. RPM (Per Gear)" or "Closed Loop Delay Max. RPM" table to 12800.
If you tuned any of the remaining tables in this table group to non-stock values, return these to stock. Failure to do so can cause switching to open loop.
- Set all the "Load vs. Rpm Component" raw values (z-axis) of the following tables to zero:
- In the "Fuel Tables" → "Closed/Open Loop Transition..." → "Transition Thresholds (Alternate)" table group:
- Set the "Closed Loop Fueling Target Final Rich Threshold (Switch to OL)" table to 4.900:1 AFR.
- Set the "Closed Loop Fueling Target Final Rich Threshold (Switch to OL)" table to 4.900:1 AFR.
- In the "Fuel Tables" → "Closed/Open Loop Transition..." → "Transition Thresholds (Delay Active)" table group:
- Set all the Calculated Load (g/rev) values (z-axis) in the "Closed/Open Loop Transition with Delay (Min. Load)" table to their maximum value.
- Set all the Calculated Load (g/rev) values (z-axis) in the "Closed/Open Loop Transition with Delay (Min. Load)" table to their maximum value.
In the "Fuel Tables" → "Open Loop (Primary)" table group:
- Tune the "Primary Open Loop Fueling Base" table(s) as you would normally just in case you have an issue with the car switching to open loop unexpectedly (or if a sensor failure or similar causes full-time open loop failsafe).
- Change the "Primary Open Loop Fueling Min. Enrichment (Pre-Final)(Force OL) Activation Threshold" table to 65535. Note: Not applicable to 15 WRX Post-recall 1 or 14-15 FXT ECUs.
- Tune the "Primary Open Loop Fueling Base" table(s) as you would normally just in case you have an issue with the car switching to open loop unexpectedly (or if a sensor failure or similar causes full-time open loop failsafe).
...