Overrun fuel cut causing RPM bounce?

[Eric S]

Hello hello hello.

I can't seem to get rid of violent car jerking when overrun fuel cut deactivates while coasting (in gear) to a stop -- this jerking motion is amplified when AC is running.

If I apply small amount of brake when overrun fuel cut transitions from active (>1600rpm) to inactive (<1600rpm), the rpm drop is smooth but still can feel the car wanting to accelerate for that brief moment as fuel cut deactivates and injects fuel.

As soon as rpm drops below as per the deactivation table (1600rpm), it injects fuel but that brings up the rpm above 1600rpm which cuts fuel, then drops rpm below 1600rpm only to squirt to bring the rpm backup above the deactivation rpm; the cycle repeats 3-5 times before finally settling to idle.

Tried playing around with the overrun fuel cut settings, but having no luck. Attached the setting file and can provide the log file through Dropbox due to file size.

 

 

 

Edited October 4, 2021 by Eric S
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[essb00]

What's your Torque Reduction/Introduction Time and Ignition Retard? You can smoothen it out by playing with those two.

[Adamw]

Give it more retard and more introduction time.  I have -20 retard and 1.5sec introduction in my car for reference.

[Eric S]

2 hours ago, essb00 said:

What's your Torque Reduction/Introduction Time and Ignition Retard? You can smoothen it out by playing with those two.

Current setting is:

Thanks you fellas, I was starting to think there's something else that was causing this Will try giving it more retard and more torque reduction time.