2002 Chevrolet Wheelchair Van

This is a wheelchair van with the 6.5 diesel. It has 153,552 miles on it. It runs and drives but has had an ongoing issue with the engine working good for a short period and then acting up. We had a lot of work done to it but it continues to have the same issues. The wheelchair lift was just serviced by Rohrer Bus. The tires were all new with very few miles on them. According to records it had a new pump and injectors on 03/11/25 and a new crankshaft sensor on 09/08/25. The AC is not working, it used to need charged occasionally.