Q: AC makes hissing noise and doesn't blow cold
I purchased a pre-owned Bravada. The car has an issue with the AC not working correctly. When I turn it on, it doesn't blow cool air at all and it starts making hissing noises. What could be the problem?
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The hissing noise is due to the A/C evaporator being starved of enough refrigerant. You will need to have refrigerant and dye added to the system and the hissing will go away. Then use a leak dye light (black light) and check to see where a leak is and fix as required. If you want to have this looked at for you, a professional from YourMechanic can come to your car’s location to add refrigerant, detect any coolant leaks, and perform any repairs that are needed.
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