2013 6.7L.

Can anyone help with why the turbo is not engaging while driving?

I know that it has not failed like it did 3 years ago because the exhaust brake works like a champ.

I am doing the 200 mile relearn for a Revmax transmission.

I have the DRD tune for the trans on the MM3 and I can watch all the gauges.

Yesterday I had boost pressure registering and today just zeros.

I suspect that this is an issue with the ECM not maintaining the entire tune in its little brain.

I had ECM and tune compatibility issues in the past and replaced the old tuner and file with the new tuner and file.

Before I go off and rewrite the tune to the ECM I would like some input please.

Also will a reflash cause me to restart the relearn process on the trans?