How are your EGT's on the hot street tune? If I floor it from a stop mine will pass 1500 degrees by 60 mph. I stopped running the tune because I didn't want to melt down the motor.
So the P2074 is caused by the SCT X4 or by the ********** tunes? As I read it seems some have the same issue and others do not. Maybe the strategy code of the truck is the difference? Both of my trucks with this issue have the same strategy code.
Add me to the list. I have two 2015's with the same setup as the original poster. Both throw the P2074 codes. I just started a thread on powerstroke.org as was told updating the SCT X4 would fix the issue. Sounds like that's not the case?