So I just got HP Tuners and am starting the tuning school course. I did an upload to try and diagnose my problems.
Current mods are: 2012 CTS-V Auto
2012CTSV-MOD.hpt
LS9 cam
2.5 upper pulley
8.6 lower pulley
Airaid intake
stock exhaust
ID 850s
Full throttle runs the car feels good. Have not scanned yet) The problem is normal driving it is getting 5-7 mpg driving at 35-60. All normal cruising.It has a studder when letting off of the gas( like an airflow or fuel flow problem). Can anyone look at the HPT file to see any obvious problems. I will get a scan file soon also.