Nissan Repair: A/C, mitsubishi galant, metal shavings

Question
QUESTION: 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: Hi DJ -

Thank you for the detailed explanantion. It helps a lot.

Try this test - with A/C on max, car idling for about 5 minutes, note the temp of the supply air. Open the hood and spray the condenser (it will be in front of the radiator and also looks like the radiator) with water for a few seconds. Re-check the supply air temp.

If the there is a difference, there could be blockage in the system, such as yes, the accumulator filter. Have that replaced. Might want to flush your system and check for leaks at the same time.

Hope this helps
aloha
calvin

---------- FOLLOW-UP ----------

QUESTION: Hi again, I can't seem to find the condenser.  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.

ANSWER: Hi DJ -

thanks again for the detailed explanation.

I still would like you to spray the condenser with water. If you just take a garden hose and shoot it in the front grille, you should catch the condenser. Let me know if the A/C air temp changes when you do that.

Also, might be worth it to check your heater control valve, since the air warms up when the car warms up, it could be bleeding hot water into your A/C system. This is an in line valve located on the heater hose, close to the firewall of your car. When you put your A/C on heat settings, this valve opens, lets the hot water into a coil in the ductwork, and the fan blows through it, causing the interior to get warmer.

Hope this helps -
let me know how this goes
aloha
calvin

---------- FOLLOW-UP ----------

QUESTION: Hi again, I sparyed the condenser with water but it didn't have any affect on the temperature.  It was in the mid 80's on Sunday and Monday and the temp coming out of the center vent was 68.  The temp from the left vent was about 63 and the temp from the right vent was about 73.  Anymore suggestions based on this info?  Is the heater control valve the same thing as the expansion valve?  The compressor comes on and stays on most of the time but does that mean it can't be a compressor problem?  Thanks again.

Answer
Hi DJ -

The Heater control valve is located on the heater hose. Look in the engine and you will see 2 hoses, 5/8" in diameter, coming out of your firewall, passenger side of vehicle. If you follow them, one of the hoses will have a valve in line. The easiest way to check if the valve is malfunctioning is to run the A/C until it gets warm. Then feel the hose, before and after the valve. If both sides are warm, then the valve needs replacement.

Hope this helps -
aloha
calvin