HELP!! Air doesn’t blow hot or cold after the outside temp reaches above 70

Juanayon13

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I’ve had this mustang for 2 years now. When I first bought it, it only blew air from the defrost vents and no where else, I ended up replacing all the blend doors to fix that issue, ac ran fine. I drove from TN to WA and I was in Colorado when my car started to overheat and my ac blew hot, the issue was the thermostat housing, fixed it and my car ran fine, got to NV and that’s when everything shit the bed, ac would blow cold for a few minutes then no air at all, it would blow for a few days, then not work for a few days, this was a constant issue, bought a refrigerant bottle from AutoZone and checked the psi, it would fluctuate from 25-50 with the compressor engaging at 50 and disengaging at 25, again still no air at all, then the air would only blow in the morning when it was cooler, once it hit a certain temp it wouldn’t blow air at all, a few days ago I got the refrigerant serviced professionally, it was a pound overcharged, they fixed it and the car blew cold air all day regardless of temperature for 3 days. Then the issue came back it blew nice and cold all morning, once it hit 70 degrees the car doesn’t blow any air at all, I’ve called the ford dealership and talked to a mechanic they had no idea what it could be, googled in every way I can word it and I haven’t seen a single person with this same issue, I’ve replaced the blow motor resistor, checked the cabin air filter, the condenser and evaporator pipes are all cold how they should be, the compressor engages how it should, fuses and relays look fine, the only real issue I can say is I see the BCM has some water damage, but I feel like there would be a lot more issues than what I’ve described and the problem wouldn’t act like that depending on outside temp and it worked good for a few days once the refrigeration was serviced.
 

86GT351

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Scan for trouble codes. If there are any overheat or AC codes the computer might be telling the system to not turn on.
 

Juice

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There is only one reason I can think of that would cause AC to work, and than no air coming out of vents. Evaporator ice up.
 

Juanayon13

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Scan for trouble codes. If there are any overheat or AC codes the computer might be telling the system to not turn on.
These are the codes that came up, the air blowing is super inconsistent, as I just drove while leaving the ac on, and it kicked on for 20 seconds, turned off for 5, turned on for a minute, turned off for 15 seconds then stayed on for the remainder of the drive (about 10 minutes)

IMG_0377.png
 

Juanayon13

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There is only one reason I can think of that would cause AC to work, and than no air coming out of vents. Evaporator ice up.
Would it stop even warm air from coming through? As neither temps work when the issue occurs
 

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