Just replaced a engine in a 2003 dodge intrepidid. The engine was originally 2.7. Before the customer purchased the vehicle the engine was replaced with a 3.5 . After the customer purchased the vehicle that engine expired. The customer then put a 3.5 junkyard motor in the vehicle. Now after the vehicle warms up it begins to cut off and act as if it is out of gas. My question is does the pcm need to be reflashed?