What was found
ON FINAL APPROACH, GOT SMOKE AND HOT AIR SMELL IN CABIN. BOTH ENGINES AND AIRFOIL ANTI ICE WERE ON . AIR CONDITIONING INDICATIONS WERE NORMAL. C/A: PERFORMED AUG VALVE CHECK PER PFHB. AUG FAILED TEST. REPLACED. THERMOSTAT/ANCPTR/PILOT PRESS REGULATORS, NO HELP. FOUND AUG VALVE MODEL TG, REPLACED SAME. FOUND LEFT PACK PRESSURE REGULATOR BAD. REPLACED BOTH WATER SEPARATOR BAGS, PRECAUTIONARY.