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Q: Evaporator issues maybe or expansion valve

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My car ac was just working earlier but as soon as i turn my car back on my car started blowing hot air and im hearing a weird hissing coming from my glove box did my evaporator just break and or is it my ac expanision valve

My car has 265 miles.
My car has an automatic transmission.

A: It is normal for there to be a hissing nois...

It is normal for there to be a hissing noise from the A/C as the pressure equalizes out between the high pressure side and the low pressure side of the system. So no need to jump to conclusions about failed evaporators yet, it could be a number of less expensive issues. The first thing that should be done is to check and see if the compressor turns on when you press the A/C button. Then you need to hook up a set of pressure gauges to your A/C system. This will tell us the operating pressure, and tell us if the system is working properly or not. From there, any issues with the A/C can be determined and diagnosed. I would suggest having a qualified professional, such as one from YourMechanic, check your A/C system for you.

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