a/c blows hot air

Sounds like the compressor maybe having a problem. This guide should help

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

Please run down this guide and report back.

The AC works while at a stop or idling, but blows warm/hot while driving. The pressure gauge show the Freon to be at a psi of 45-50 on the low side. Outside temp at the time was mid 80's. Compressor kicks on and off for about 3 or 4 minutes after first starting the car. Any ideas what might be the cause of this?

Hello,

This sounds like a classic case of the system being down on charge. Here are a few guides to help you get the cool back going again.

https://www.2carpros.com/articles/air-conditioner-how-to-add-freon

and

https://www.2carpros.com/articles/air-conditioner-leak-detection

and

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

and

https://www.2carpros.com/articles/replace-air-conditioner-compressor

The low side charge port is on the hose/tube going from the firewall to the back of the compressor.

Please let us know if you need anything else to get the problem fixed.

Cheers, Ken

My car is the LT model. It stopped blowing cold air when A/C was on. Is somewhat of a hot day so I noticed this fairly quickly. Right when this happened I also noticed the temp gauge pointing on "C". No previous A/C issues as just yesterday was functioning properly blowing ice cold air. I have already inspected for any leaks, coolant is full. But both of these seem to go hand and hand (AC/temperature gauge). also, seemed to have happened randomly. Any suggestions on what this could be?

Hello,

It sounds like the coolant temperature sensor has gone bad causing both of you problems, Here is a guide that will give you an idea on how to fix it.

https://www.2carpros.com/articles/coolant-temperature-sensor-cts-replacement

Please let us know what happens.

Cheers, Ken

Like other 2008 malibu owners, i too have a problem with my ac only blowing out hot air. the car has 33,000 miles that i have put on it. why would this be if the car is still reletivly new. is it the freont?

Hi there,

The first thing to check is low refrigerant as this is often the cause of this problem, start here.

Mark (mhpautos)

Air conditioner was recharged and it took a while before becoming cold. drove about fifty miles as soon as I slowed down to turn the A/C started to blow hot air. If car is turned off then when restarted and A/C started will blow hot air until windows are put down, like drawing cool air out. Why? Possible plugged/blocked hose?

Hello,

When the cold air stops can you use a flashlight with the engine running and the ac on check to see if the compressor clutch is turning, this will help us narrow down the problem.

Here is a guide that will help

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

Please run this test and get back to us so we can continue helping you.

Cheers, Ken

it cooled really good for about 2 years, then would cool off and on, then would only cool while sitting still, now doesn't cool at all. Full of freon, the clutch cuts in like it is supposed to, the air temp control door is working like it is supposed to....the temp gauge is working, the fans are working...not sure if it is a switch or expansion valve????? 104° outside is just too hot for not having a/c in the car.....

Is the larger of the 2 hoses under the hood getting cold?
Maybe a blend door issue

THE MEDIC

hoses do not get cold....the blend door is working as designed...

How did you determine the charge was correct?

THE MEDIC

My brother charged it with freon - that is when it was cooling just when it was sitting still. I am going to have him put his gauges on it tomorrow night so I can get what the pressure readings are...that is probably gonna be a question that comes up at some point......

Heres a video on charging your system

http://www.youtube.com/watch?v=CWN6oX3jtOY



THE MEDIC

Probably not a good thing, but the high and low pressures are both at 70......

during hot humid weather AC sometimes blows warm and temperature gauge quits. seems a common problem but no common answer. car gets to temperature normally and fan comes on when AC is used. in other words no strange symptoms besides quitting. turning car off and back on does not cure it. check engine lights when this occurs. Also had code read and p0128 was only code. But thermostat looks to be behaving correctly! This problem only shows on hotter than normal days over eighty degrees and humid. Temperature gauge wiring looks okay, although plastic harness shielding is rotted away from heating. AC system has never been touched from original, car has never been wrenched on other than brakes tires oil changes. When it works it blows cold.

Hello,

This sounds like a classic ac compressor clutch coil that is failing. When the AC is blowing warm check to see if the clutch is spinning.

Here are a few guides to help you get the problem fixed:

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

and

https://www.2carpros.com/articles/replace-air-conditioner-compressor

Please let us know what happens, we are interested to see what it is.

Cheers, Ken

what i would like to know is if and where there is a relay for the compressor?

Here is the fuse box (below) with some guide to help you do some testing

https://www.2carpros.com/articles/how-to-check-an-electrical-relay-and-wiring-control-circuit

and

https://www.2carpros.com/articles/how-to-use-a-test-light-circuit-tester

Please let us know if you need anything else to get the problem fixed.

Cheers, Ken

Recently, the air conditioner stopped blowing in our car so we took it into the shop. They said it was a relay issue, causing the compressor to not kick on. So they replaced a "harness". After getting the car back, It worked for a few hours, but I noticed it was blowing luke warm air every now and then. So I turned it onto the indoor circulation and it was getting cold again. But I also noticed that when turning off the car, often the next time we drove, it was back to luke warm air again. Sometimes messing with the buttons got it working and sometimes messing with it did nothing. So I dropped it back off at the shop, only for them to inform me they left it running and it was blowing cold air. Therefore, it seems to them like nothing is wrong with it. So I need help figuring out what this could be, I am not really car savvy but I do know the general basics(or can learn by other means). So here is what I know/did so far: Car stops blowing cold air(bought a refill of refrigerant), was blowing cold air when filling, as soon as I drove no cold air, took it into the shop (told a electrical relay issue not getting to the compressor) they replaced the harness, When driving it is now randomly blowing luke then cold air. There are no lights indicating that it is turning off and on, it just turns to warm air/cold air at random times. The other day in stop and go traffic it completely stopped working, likewise to the turning the car off.

have the hvac unit scanned for codes and do a performance check on air conditioner unit. sounds like it is freezing up from to much moisture in system.

ac doesnt blow cold air,everything was fine just one day no cold air,it blows air all the bottens work, but no cold air,what could it be?

Check to see if the compressor clutch is engaged when A/c is turned on. It could be the compressor that is faulty or a control fault.