I had an engine fire on my 01 Grand Prix 3.8 and decided to fix it bought a used engine and swapped wiring harness and upper intake and other engine parts damaged in the fire. Now I have it running and am getting OBD2 codes PO102 Mass Vol. Airflow Circuit Low Input, & PO443 Evap. Emissions Control System Purge Control Valve Circuit. Also AC is not working now Clutch not engauging, it was OK before the fire any input as to what may be causeing these codes and AC problem is appreciated. Thank You ttrech