throwing the code 0641 truck runs terrible and stalls out wondering in dummy terms how do I fix it?

Question

1.friend unhooked plug wire and then hooked it back up. Now my truck runs terrible and stalls and files rough

Answer 1

P0641  5 Volts Refference Circuit

There are 2 sensor that codes up P0641 , The MAP (manifold absolute pressure)  sensor and the EOP (Engine oil pressure) the PCM has detected that the 5 volts is out of tolerance, Its the voltage supply to the MAP sensor that is contributing to this condition. With key on engine off, with the MAP sensor disconnected measure the voltage of the MAP sensor 5 volt refference it it measure 4.8 to 5.2 volts (GRY wire) . Replace the MAP sensor. Do this with the EOP disconnected.