Originally Posted by
Ben Diss
What's probably happening is that the desired idle RPM is being reached quickly and overshooting slightly. Idle proportional adaptive is kicking in too aggressively causing the idle to jump back up. The inverse is happening trying to bring it back down.
Try this.
Under Engine/Idle/Idle RPM
- Idle Proportional Airflow vs. RPM Error: In the coastdown row, left of 0 RPM, set all values to 0. Right of zero, multiply all values by .5.
- Idle Adaptive Airflow vs. RPM Error: In the coastdown row, multiply all values left of 0 by 2, multiply all values right 0 by .25.
If that makes a difference, put the old values back and verify what you think you saw. Then go back and play with different multipliers and see what works for you.
Post your tune and a log file of this when it happens and we'll be able to offer better advice.