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Q: I think my AC is broken.

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I don't know if the compressor is what needs replacing. I was driving the other day with the AC on. I noticed the car was struggling to accelerate and the AC seemed like it was chugging. When I got home, it smelled like something was burning. I took it to get the AC diagnosed and was told that the AC system was on low charge at the time. But I was also told that recharging it wouldn't guarantee that it would be fixed. I was also told the vent temp was 60 degrees, low side pressure was 35psi, and high side pressure was 250psi. Ambient temperature was 85 degrees. I don't know what to do. The belt is fine, and I haven't had this issue before. I am debating whether or not to buy a new compressor, drier pad mount, and expansion valve, and just have it all replaced and recharged. Any suggestions?

My car has 122000 miles.
My car has an automatic transmission.

A: It is difficult to know what is going on he...

It is difficult to know what is going on here. Mainly because the A/C system would only cause your car to struggle on acceleration if there were an excess of oil or refrigerant in the system or if the compressor was failing. With what the repair shop has stated, I would think they would have had an idea of what other problems your A/C system has. The pressure readings seem ok except the low side seems a bit high, of course the temperature out the vents does not seem cold enough. This indicates the A/C is working and the blend door is not.

Measuring the temperature of the low side is what I would do next here. Usually simply grabbing a low side line is all I need to do. If the low side is indeed problematic, this would indicate a compressor that isn’t compressing as it should. But I wouldn’t condemn it based on this information.

The blend door is part of the dash and not the A/C system under the hood. This would seem to be the reason they said the A/C may not blow cold. The blend door is part of the temperature control system in the dash panel. This is a separate system from the A/C system under the hood.

The diagnosis of the A/C system requires a number of hands on visual inspections. At the moment, I don’t see enough information to give advise about why your car would be chugging.

If you need some help with this, consider booking an appointment with a certified mechanic to help you more thoroughly diagnose the issue with your A/C.

At the moment I don’t see a connection between your chugging and the A/C system. There could be one, but I just don’t have enough information at this time to give anymore advise.

Thanks for your inquiry.

Good luck!

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