My girlfriend has a 2003 eclipse and is having a/c issues lately. It blows hot while at idle and cold when driving. After doing a lot of searching around online I found that it more than likely was either the fan on the condenser wasn't working or low on freon. Checked and the fans are working.

I thought that the air only blew cold when driving but noticed yesterday that while in park i pressed the gas and the air started blowing cold. this would rule out the idea of forcing more air over the condenser is helping to cool the air to me.

If anyone has any ideas on what could be causing this I would really appreciate it. Thanks in advance!!

Well I know the serpentine(or accessory belt) drives the A/C compressor, so when you give it gas that belt is spinning faster. Maybe she needs a new compressor since it is only getting the proper power when the serpentine belt is spinning faster, and at idle the belt isn't spinning fast enough to power it properly hence the hot air. It's just a theory so don't get mad if I'm wrong.

The belt that drives it could be slipping

or....

You may have a problem with one of your AC lines. They are made of cheap, thin aluminum. It might only blow cold when you are revving beause more air is being forced through those lines.

Is time for you to service the a/c. take out the coolig coil wash it with chemicla, change the expansion valve, and filter, vacuum out the air and water vapor in the system and refuse the freon.

anyway don't try it untill you change your condenser. your problem is the conderser has chock. uselly, the hot gas from the compressor pass through the condenser line is to dissipate the heat, so when either 1 or 2 line has chock, than it will not enough to dissipate all the heat, when the car under idle. Hot gas need to fully dissipate away the heat during it pas through the condenser, othwise when the gas expan inside the cooling coil it will not enough to absorb heat from inside the car. that is also why you feel the air is hot when car is under idle.
next, over top freon gas also can the same problem. reason over pressure . next time when you go top up freon gas you must make sure the weather is at least 28 degree. dont ever top freon gas at the morining or at the night or inside the contain. idealy is under the hot sun.

These cars are notorious for leaking freon on the high pressure line from the compressor to the condenser at the top left of the condenser standing in front of the car, or on the high pressure line where if converts from metal to rubber coming off the compressor. This sounds like the freon is low, this does not allow enough condensing at the condenser where the high pressure gas is converted to a liquid, when the freon is low it take more air flowing across the condender to convert this gas to a liquid. It you have a manifold gauge set hook it up and check your pressures, there is a chart for R-134a that will tell you what pressure you should have on the high side at different ambient tempertures. Let me know if you need this chart. If you disconnect the system for any reason make sure you pull a full vacuum on it before recharging, this will remove any moisture since moisture turns to a vapor at 60 degrees fahrenheit under a full vacuum.

i agree with what 03gsecliopse has mention, but the a/c systems uselly has equip with a low pressure cut-off gate, this gate is to protect the compressor for demage when the gas leak.

Anyway it is also batter to have a checking gas leak for your system before send in for service. to verify the gas leak of your a/c system, first, you must prepare a sponge with soap water, than you can start to check the whole a/c pipping condenser and filter, if you can see any oil surface on your a/c pipp especially the join of the a/c pipping, you than apply some soap water onto the join, if can see bubble on the join, than that is the portion where the gas leak, if at the engine compartment you can't see any gas leak, than too bad, you got to disassembly the cooling inside the car. a new cooling coil usually can only last for about 5 to 7 years, and some only 3 years.

looks like you will have to get that sucker recharged. and it wont be the same either

If it is blowing cold they it may not be tripping the low pressure switch. I used a can of freon with UV dye in it and pull my car in the garage where it was dark and used a standard black ligh bulb to find the origin of my leaks, it works very well, the can of freon with dye is $9 at Advance auto.

FREON is r12
R134a isnt known as freon because r12 was dangerous to the enviorment.
Slipping is my guess If u Dont hear the motor bogg down its going bad...
the thing is the compressor engages by a magnet basically thats why you hear the clunk.it does go bad. o well thats life just get one off of ebay.

3dsmerGS did not read the post, the speed of the engine doesn't engagae the clutch, your clutch is not the problem. Low charge is the problem and since 3dsmerGS wants it to be technical, you are low on Tetrafluoroethane.

Your also wrong.
When hes driving is the only time it works.
If it was low it wouldnt even start up both lines would be super warm.

as what i say, every A/C systems will equip with 1 low pressure electric gate and 1 high presesure electirc gate. when the A/C gas is low too low the low pressure gate will automatically cut off the A/C system, and when is over A/C gas pressure, the high pressure gate will also cut off the A/C system. this is to help protect your A/C compressor for damage. but sometime when the gas is not reach to the stage of too low a/c gas pressure, the low pressure gate will not cut off the A/C system. and this will be the situation as mention. low A/C gas and need to increase the engine RPM so that the A/C compressor can circulate and compress more A/C gas to collect more heat out from inside the car and create cool air. I believe there is a leak of A/C gas, and i also thinks 03gsecliopse is correct the A/C gas is low.

A/C systems not only neeed a/c gas, but also need lubricant oil for the compressor. so when there is a leaking, you can see very obvious oil surface on the leak portion of the A/C pipping.

you do know refrigerant doesnt become a gas until its sent the the system and working......
its a liquid dude. u tryed a little too hard. sry.

Alright, please tell me how to top-up " refrigerant " into the A/C system? is through the discharge nipple nose or through suction nipple nose?

1) Discharge line (nipple nose) is high pressure line. Is hot compress gas after compressor compress. this line is transfer after compress hot gas to condensor for remove heat n condensing it into liquid foam =Hot gas. That is also why A/C system need a fan at the condenser area.

2) Liquid line after the condenser, at this stage than gas were turn into liquid. this line than carry liquid into the cooling coil. liquid pass throught the expansion valve and expand into gas (Low Pressure) Due to the change of form, surrounding heat will be absorb by the gas inside the cooling coil. that how the hot air from the blower fan, blow throught the cooling coil and turn cool air

3) Suction Line (nipple nose) is low pressure line. this line is carry the cool gas with absorb heat from after cooling coil, back to compressor for compress.

4) Only Gas can be compress into liquid, and liquid cannot to be recompress.
that is why A/C systems need a compressor? ( is to compress gas and heat into hot gas before turn into liquid)

5) When A/C System is off the "refrigerant" inside the A/C system is gas form. When the A/C system is ON than the compressor compress gas into liquid form.

6) In the complate A/C system liquid are only 25% to 30% form and 75% is GAS form