- 1). Start the engine and allow it to warm for five minutes. Turn the air conditioning until to medium and open the hood.
- 2). Apply spray brake cleaner to the base and tubes of the air conditioning unit. Look for any air that's forcing the brake cleaner away from the unit. Once you see the air blowing the brake cleaner, you have located the leak.
- 3). Mark the leak with a marker and allow the brake cleaner to evaporate. Turn the engine and air conditioning unit off.
- 4). Place a small piece of steel putty to the damaged area on the air conditioning unit. Smooth the steel putty with your finger so that it is flush with the metal on the unit. Allow the putty to dry over night.
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