ISX15 450 Delete issues

[Motorman Steve]

I have a customer who brought me in a 2011 volvo with an isx15. It wasn't showing oil pressure, had a pump failure, replaced pump and lower bearings. Dash would not show oil pressure while the ecm would show voltage changes on the oil pressure circuit. Had a guy remote into the ecm to update the callibration to correct the oil pressure issue with the dash. Now the dash shows oil pressure but the engine runs like shi#t. Its loading up on fuel and smoking really badly. It was deleted previously so i could not send it to a dealer. Im not sure if the guy installed a factory callibration or if the delete tune is bad. I am at a loss, any information would be incredibly useful.