Idle runaway with DBW on JRR 2JZ firmware.

[Suprafied]

All,
I've been battling an idling issue with my car with little to no luck on finding the issue since the car. I've been running John Reed's 2JZ firmware since 2014 with no such issues on my car and a few others I've built for owners.

The problem I’m experiencing is:
- Upon start up the engine speed will race to 2500rpm without any control.
- The idle mass feed forward table has no influence to control idle RPM

Now, the only way I've been able to control idle is to:
- Limit the idle actuator throttle aim maximum to 10%
- Limit pedal translation to 6% for anything above 5% of the total pedal stroke (0-100%)
- The ECU is retarding timing to -3 to- 9 degrees vs. what historically (9-15 deg with a target of 20-deg).
- Lambda holds at .90 with or without closed loop fuel control active.
- Idle state will activate along with ignition timing state showcasing “Idle”.

To date the following has been verified:
• Engine mechanical timing
• Coil pack and igniter resistance along with correct firing per M1 configuration
• Cam and crank sensor resistance along with verified its position through the built in M1 oscilloscope.
• Lexus SC430 pedal and Hitachi 75mm Throttle body setup according to M1’s guidance.
• Swapped M150 Ecu with another working unit.
• Injectors cleaned/verified by Injector Dynamics
• Continuity to all the electrical connections above have been checked.
• Replaced jumper harness and factory harness to rule out any additional influence
• Boost leak tested the entire assembly to 160kpa with no leaks. There was some thought at major vacuum leak was a cause.
• Compression test was 160psi across all cylinders
• Upgraded to latest firmware for the 2jz from John Reed and even started multiple tunes from scratch to no avail. I am currently running Rev 01.02.0006 now even though I tried 01.03.0002.
Attached is the log file from this situation I noted above. Overall, I’m looking to understand what else may cause the ECU to run away at start up.

[SOReilly]

Hello,

Without log data we could only guess.

As this is a JRR firmware the developer is responsible for providing support, have you contacted your MoTeC dealer?