Deleted and tuner

[Ataylor67]

Got a 08 6.7 cummins deleted with a H&s mini maxx. Do I need the tuner on the truck with the it being deleted for it to run right?

 

[Scottly]

You shouldn't. The issue you have is that it's SOMETIMES hard to know if it's the tune or a component that's causing issues, because many of those "tuners" wipe out the factory fault parameters, so no codes will pop to alert you of any known faults. If I were you, and it's been running OK prior, I'd make the assumption that the tuner isn't the issue and I'd start diagnosing possible component failures.