[Phinatic]

I haven't had any issues with my '09 SRT with a Stage II ProCharger. I live in Aurora and using the same tune I used when in Germany. However, I haven't gone WOT.

Did you install high-flow cats or mess with your O2 sensors? I assume you're in closed loop when experiencing this issue and not rev'ing the motor in a lower gear? Sounds like the PCM is not getting feedback from the O2 sensors. I would also check your MAP sensor.

 

[Phinatic]

I forgot you had to change out the PCM with the '13 since they couldn't modify the tune due to encryption. I thought you had to change out the harness also?

I'm with SRT8Tech, in that it sounds like the PCM is keeping static data and not using the adaptive data. Have you tried to disconnet the battery for 45 minutes at the altitude you're having issues at and then drive around at that altitude? If it runs OK at that altitude but has issues when you descend, then I would say your PCM is not making adjustments to the adaptive data it's receiving (or not receiving).

Also, do you have an wideband sensor installed to measure AFR? If so, what are the AFR readings at the different altitudes?