For 1990-2009 cars

Symptom | Cause
--- | ---
Important: Under certain high humidity climate operating conditions, a musty odor may develop due to microbial growth in the evaporator area. This odor is generally temporary and as climate conditions change, this condition will disappear and repair on its own. However, if mold or mildew odor continues. Refer to Odor Correction .
Musty Odor |

• | Interior water leaks exist in the body. Seal the body. Refer to Localized Testing (Spot Testing) and Body Waterleak Repair in Waterleaks.

• | The evaporator drain is clogged. Clean the evaporator drain.

• | Mold or mildew growth in the evaporator fins. Remove the evaporator and clean the evaporator fins. Refer to Evaporator Core Replacement .

Coolant Odor | A coolant leak exists. Inspect the heater hoses and heater core for leakage. Refer to Loss of Coolant in Engine Cooling. Refer to Heater Hoses Replacement and Heater Core Replacement .
Refrigerant Oil Odor | Refrigerant leakage at evaporator. Inspect evaporator and fittings for leakage. Refer to Leak Testing .