'02 Dodge Dakota 3.9 Chugging

My roommate has a 2002 Dodge Dakota Sport with the 3.9L V6 that has basically been a nightmare since he bought it new. It’s at ~70,000 miles. Recently he has had a new fuel pump, new catalytic converter, new plugs and wires, a new waterpump (probably unrelated to the issue), and a new O2 sensor. This was all done at a dealership last week. Today the truck started chugging periodically and losing power and kicking on a check engine light. He’s hesitant to bring it back to the dealership because they charged him an arm and a leg and had the vehicle for over a week.

Any ideas?