I have a 6.7 that has had all deletes with mini maxx. I have recently noticed when trying to maintain a speed and when accelerating around 2000 rpm it's like the tach sticks and I can feel a little hesitation. I have had a mechanic look at it and they replaced a fuel sensor but didn't help. He couldn't figure out anything else on it. I did have a code for a circuit high cooling fan. I'm new to these forums and didn't know if I could get pointed in the right direction on this.