A/C suddenly blowing hot air

STEFANIERIDDLE76

MEMBER
2008 CHEVROLET MALIBU
2.4L
4 CYL
2WD
AUTOMATIC
230,000 MILES

A/C working fine then one day starts blowing warm air. Took car to Big O tires for free A/C check, they said expansion valve needed to be replaced and so I did. But I remember on the paperwork that the guy doing my A/C check gave to the counter person had this "expansion valve, E and C" the estimate he gave me didn't say anything other than thermostatic expansion valve, labor, Freon. I've replaced the expansion valve, tested all relays, fuses, compressor working properly and condenser. Help, I live in the desert and it's too hot for no A/C.

1 Reply

KASEKENNY

MECHANIC
18,907 POSTS

Okay. We need to check A/C pressures at this point because if the compressor is working and it is still blowing warm then we need to make sure the pressures are correct. The fact that they said it needed the valve tells me the pressures did not appear correct to them and they assumed the valve was the issue. More then likely the high and low are pretty even and that would indicate the compressor is actually not pressurizing the Freon.

So let's start with the pressures with the engine running and A/C on and go from there. Thanks

https://www.2carpros.com/articles/car-air-conditioner-not-working-or-is-weak

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