Skip the auto shop - Our mechanics make house calls

Q: I think my AC is broken.

asked by on

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.

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!

Was this answer helpful?

Need advice from certified mechanic? Get help now!

Over 1000 mechanics are ready to answer your question.
The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details

Ask a Mechanic
(100% Free)

Have a car question? Get free advice from our top-rated mechanics.

Ask A Mechanic
Over 10,000 questions answered!

Get an instant quote for your car

Our certified mechanics come to you ・Backed by 12-month, 12,000-mile guarantee・Fair and transparent pricing

Get a quote

What others are asking

Q: Front AC not working

Hi. Sounds to me that the actuator for the AC is not functioning properly. I recommend having a mechanic properly inspect and diagnose your AC issue. They will be able to let you know what replacements and repairs need to...

Q: Mazda 6 reliability

While we are not permitted to endorse certain makes and models of vehicles, we can tell you there are several other websites that not only have customer reviews, but also list the common problems. Often you can find great information...

Q: Replaced alternator on car 2 times each time shows it's charging 14v let car run for a little bit then test drive and car voltage

There are reports that the replacement alternators will not communicate with the engine computer and will not charge correctly. I recommend using only the manufacturer approved replacement part. It can be new or remanufactured but approved for use in the...

Related articles

P0052 OBD-II Trouble Code: HO2S Heater Control Circuit High (Bank 2 Sensor 1)
P0052 code definition HO2S Heater Control Circuit High (Bank 2 Sensor 1) What the...
How to Avoid Back Pain in a Car
If you have back problems, sitting in a car for an extended period of time can be excruciating. Even without back problems, you could experience discomfort and soreness from...
How Much Does a Mechanic Make in Vermont?
Automotive technician jobs in Vermont have an average mechanic salary of $37k, with some mechanics earning a salary of $53k.