Hot air from the AC vents is a sign of a low refrigerant level (R134A) in your car AC system whereas, low or no airflow from the AC blower can be an issue with the evaporator coil or a dirty air filter, clogged drainpipe, or a broken fan blower inside your car AC vent. We highly advise you to get your car AC thoroughly diagnosed at the nearest GoMechanic workshop in Malaysia.