QuestionQUESTION: Hi, I have a 2001 Mitsubishi Galant which I just purchased about a month ago. The A/C isn't blowing that cold. A mechanic looked at it quickly and put some R134a in it (since it was a little low) but it still isn't blowing that cold. The other day for example, it was almost 80 degrees outside and the temperature at the center vent was mostly around 68 degrees. There was a point where it was blowing at 56 degrees but it only stayed there for a couple of minutes and then went back to 68 degrees. The other day it was 90 out and the A/C temp was about 77. Today it was 60 out and the A/C temp was 44. The A/C was always in recirculate mode and I heard the compressor kick-in every so often and the fan was set to speed 2. When I set it to 3 or 4 the temperature would go up about 10 degrees (I guess because it was adding in warm air). Also, the A/C temperature didn't change much when I was idling as compared to when I was driving. Also, the low pressure line under the hood was ice cold. Other cars that I have had had very cold A/C's. Is it possible that this model car just doesn't blow as cold as other model cars? I read on the Internet that sometimes metal shavings can partially block the line and divert the cold air. Could this be the problem or do you have another suggestion? Thank you for your time.
ANSWER: There's no question something is wrong with your air conditioning. Vent temperature should be below 50F when 90F outside.
There could be any one of a host of problems with your a/c system. It'd be my recommendation to have it looked at by a qualified a/c mechanic with the equipment to perform a/c work properly.
Just based on your description, it sounds like the refrigerant charge could very well be low; you say the compressor only turns on every so often. So if I were looking at this, the first thing I'd be likely to do is to make sure the system is charged with the specified amount of refrigerant, not simply adding a little to see what will happen. If low, I'd expect that installing the proper amount will restore the system to proper function, but I'd also expect that there's a leak somewhere causing the low refrigerant issue to begin with. So I'd also install dye into the a/c lines and instruct you to return when the a/c blows warm again. This way, the leak can be detected with a black lamp and then repaired properly so the system will no longer leak.
If the refrigerant level is proper, then it'll be important to check the gauge pressures to determine whether there's a blockage in the system. In this situation, the high pressure side will be close to normal while the low pressure side will be very low or even have a vacuum. It'll also be important to check the necessary electrical circuits for compressor operation.
Lastly, I don't have any specific experience with your vehicle make and model. Anthony
(http://www.allexperts.com/el/Mitsubishi-Repair/)
may be able to provide better information on common problems on your vehicle.
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QUESTION: Hi again, my mechanic said he removed all of the refigerant and filled it up again with the proper amount since he thought that is was overcharged. It does blow a few degrees colder but it still isn't that cold. Yesterday it was about 75 degrees out, but the A/C temp was about 55 degrees at Fan Setting 2. At Fan Setting 3 the A/C temp is about 60. At Setting 4 it is about 62. That is without recirculation on. When I put it on, the temp goes up about 2 degrees or so which is strange to me since it should go down. The A/C compressor seems to be cycling normally. There is something else that I noticed that may be causing the problem. When I first start the car and put the A/C on it blows pretty cold...about 45 - 50. Then after about 3 minutes or so the temp goes up to 55. Also, when idling, when I just put the vent on (no A/C) the temperature of the air coming out of the vent is about 90 degrees (even though it was only 75 degrees outside). The temp control was on the coldest setting. Now I am thinking that possibly once the car heats up after 3 minutes the A/C is working very hard to try and cool that hot air that is coming in. If this is true could this problem be Heat related...such as a blockage causing extra heat to come into the car. By the way, do you know how much refrigerant this car should have? Any advice or suggestions would be greatly appreciated.
AnswerYou may have a problem with the blend door in your heater box or the cable that controls it. This door regulates the temperature based on the position of the lever (or knob) on the heater control.
In addition, I'd be interested in knowing the gauge readings when the system is at rest and when it's operating. I understand you probably don't have A/C gauges, but your mechanic should have them.
