Random lean spikes after letting off throttle

[ferocity02]

I installed a 4L80E and a new converter and noticed an issue on the highway. Sometimes when I let off the throttle I will get a very lean spike, almost like the engine it trying to die, but it will catch itself. Sometimes it happens many times in a row. It is more common after some medium-heavy throttle.

Fuel pressure looks good, but the IBPW drops very low causing the lean spike. And ideas where to look in the tune for a cause?

I had a T56 before and it never did this.

[5.7ute]

Hi Mike.
I would first check all of your DFCO settings.
Also log G/CYL to see if there is a glitch in the airflow model causing it to command such a small pulsewidth.

[ferocity02]

Mick,

DFCO is disabled at the moment.

I'll log airflow tomorrow morning.

Here is the log that screenshot came from. It's mostly trans PID's.

[5.7ute]

Mick,

DFCO is disabled at the moment.

I'll log airflow tomorrow morning.

Here is the log that screenshot came from. It's mostly trans PID's.

No worries.
Send the tune file through to my email if you don't want to post it up.

[ferocity02]

Durrrrr. DFCO was enabled. I had disabled it in different tune to work on the VE table :wallbash: