Reaccion

Hello guys! I own a 1989 Honda Civic 5 door automatic. I have a BIG problem with my AC. I have to start up by mentioning that I had to ad Freon every 6 months to my AC system and the AC used to work poorly. I added the leak detector Freon but I did not notice any leaks anywhere (No lines, compressor, or condenser leaks). Now I tried putting Freon. But my AC still was not blowing that cold, especially when it was at idle. There was a time in which my wagon’s temperature was going over its normal position. I checked the AC and radiator fan relays and one of them was a little worm out. I changed but the problem continued. Since I had changed the expansion valve some time ago, I decided to give it a double check. The expansion valve was not too tied to the evaporator. I cleaned up the expansion valve and re-tied to the evaporator. This time, I used two tie wraps. I also checked the drier and it seemed fine. Of course, the AC system needed to be recharged. I added a 12oz R134A plus half of another 12oz can. At the beginning, the AC did not feel cold. But after a little while the AC started getting cold. The air was not that cold but good enough. After using the AC for a couple hours, I noticed that the AC started to make some noise. I checked the AC compressor and its clutch was engaging on and off. I check the low pressure line with the gauge and it was showing that there was over pressure and redlining on and off. I released a little pressure by opening the low pressure valve. I noticed that compressor problem got better and the AC started to feel better but not that cold still. I checked the AC compressor and it seemed oil spread at the compressor and surroundings. Now, I check low pressure line with the gauge and it shows low pressure or low refrigerant. The AC blows slightly cold; well I would say almost nothing. I took the car to service the AC system and the mechanic suggested me to change the compressor because of the oil spread at the compressor. As of now the AC still blows minimal cold and I could notice that the eye glass on top of the drier shows Freon circulation.


I bought a remanufactured compressor which came with a new drier, new oil PAG, and O ring set. I installed the compressor myself and put 8OZ of the PAG oil in the compressor. This time, I did not even want to fill the system myself. I waited until an specialist had the system vacuumed and refilled with 1.6Lb of R134A refrigerant. The AC worked just fine (Not perfect but a lot better than before). But by the time I got home, the AC had lost its power. The AC was blowing very little cold again. I went back to the specialist and pointed to me that there was supposed to be a leak in the system. He was right. One on the hoses near the AC compressor was leaking (even though we found the same weight of refrigerant when the specialist did the system recovery). He fixed the leak, vacuumed and recharged the system again. The AC was blowing cold. The specialist pointed to me that the AC should have been colder. But to get the AC work the right away, I needed to install a new expansion valve. The temperature at the middle AC vents was 55-58 degrees. This was the coldest I ever felt the AC and I was really happy with it. Then, again, by the time I picked up my wife the AC started blowing a little warmer. After 15 minutes of driving, the AC was blowing warm again.


I have not taken the car back to the specialist yet. I am really confused now. It seems that I have covered all the bases but there are still problems with the AC system. Please help me out!!!!!

Summary Update: The AC blows cold when I first start the car and AC system. Then after 15-20 minutes, the air conditioner begins feeling warm/humid. The A/C will not change back to normal cold until I turn off the car and let the car sit overnight. It is only when the AC blows cold for about 20 minutes and then go back to warm/humid.... Please help me!!!!!

sumdewd

I don't want to sound like an ******* here, but there was more than one thing that went wrong. The Matsushita system takes a maximum of 5 ounces of oil, and that's only if the whole system is bone dry. This will contribute to cruddy idle vent temps.

It also sounds like you used a cheap walmart a/c dial gauge. You need to use an a/c gauge manifold set to get good readings.

Another thing is the oil around the compressor. That's typically a shaft seal which means you should replace the compressor.

I really don't have time to go into detail because I need to leave for work. There were more things I noticed but I have no time to write it out. I will read it further and try to help out later on.

Reaccion

I searched online and I found out that the system needed 7.5Oz of oil... I searched wrong then How could I drain the system out??

The readings were taken with a professional machine and mechanic.

Yes, there was oil around the compressor. As you may have read, I changed the compressor.

I hope to hear from you again later. Thanks...

91 EF DX

are you sure the evaporator coil is not leaking?

pimpwagon

how long did the system hold 29inches of vacuum for before the refrigerant was put in? That should have told you everything you needed to know abut the leak.
please say you pulled vacuum first. if not, you have air mixed in with the 134a which will make the system work like *****. the air will displace the refigerant needs and your pressures will get wacky on both the high and low side. any time a line is removed the o ring should be replaced and lubricated to seat properly. they are cheap and make a world of difference in how long it works for after repairing.

4drEF

Seems you have another leak.
Did the "specialist" put UV dye in the system?
Makes it really easy to see where your leak is.

If you have to evacuate the system again, you might as well put the expansion valve in while you have the chance.
R12 filled and R134 filled valves are pretty close, but if you are going for the best you can get it, then might as well do the valve.
They are inexpensive too!

sstupid

Anyone have a pic of where the expansion valve is?

diesel_tech

unless you replace the entire system, do not use the recommended amount of oil. THe system does not need that much oil.

4drEF

This pic is of an Accord I think, but they are all in the same place.

sumdewd

You said you zip tied the expansion valve... Its sensing bulb MUST be wrapped in A/C tape and affixed to the evaporator outlet pipe. A/C tape is like a thick tar type tape that sticks to itself and insulates the bulb so it only senses the evaporator outlet temperature.

In addition to replacing the compressor, you should do another receiver drier and flush the heat exchangers so you know exactly how much oil you have. Weigh the oil in. Too much and you get poor cooling and compressor slugging (hydrolock kind of). Too little and the compressor blows.

If you haven't guessed yet, A/C systems get real expensive and tedious REALLY fast. I would honestly pay a friend in beer and pizza if you have one that knows their stuff with A/C. A/C systems are EXTREMELY picky with how you set them up.

Make sure both condenser and radiator fans are running whenever the A/C system is on. Also make sure the fins are clean on the condenser, radiator, and evaporator.

And don't even bother charging it back up until you find the leak or you will have to start from scratch yet again because you will have an unknown amount of oil if there's still a leak.

Buy a set of A/C manifold gauges if you charge yourself. You don't need it if you have your dude evac and charge it. Walmart ones WILL NOT WORK.


As for it blowing warm again... Has it worked cold since? Or did it stay warm forever? I need more info to give you more help.

Reaccion

I changed the expansion valve myself and at that time I added a leak detector bottle. I have not noticed any leak at the evaporator coil.

Reaccion

Thanks for replying... The mechanic vacuumed the system with the machine for about 30 minutes. It seemed that there was not leaks at that time. I added 8oz of PAG oil and I changed the O rings at the compressor and at the drier. However, I did not change the O rings at the expansion valve nor at the evaporator.

Reaccion

Thanks for replying... The compressor was totally empty. I thought that I could ad the whole 8oz oil bottle :-/

Reaccion

Wow, I did not know that... That should be a real issue there. Since the expansion valve is not properly set, it would not probably work correctly letting the cold air on and off....

Reaccion

After buying and installing the compressor, I also bought and installed a new drier/receiver.

You are right about how tedious the AC system is. That is right I paid this mechanic to vacuum and recharge the system for me.

I will check to see if the fans and relays are properly working. I have noticed though that when my 2006 Civic AC is on, the fans are constantly working. In the other hand, my 89 civic last a lot longer to have the fans working when the AC is on...

I will not charge the system until I find the leak. I am even scared to go back to the mechanic. Every time I see him, I end up paying more money and I get out of his shop with a cold AC until 3 hours later :-(

Before I changed the new compressor, I was using an AutoZone gauge to measure the AC system. After that, I have had my SUPER mechanic do it for me...

Reaccion

The AC blows cold when I first start up the car. the problem begins when is too hot outside and my car is driven for a while.

I remember the first time the mechanic charged the system, the AC blew cold. I went to my house, picked my wife and when I turned on the AC the system was working poorly. When I took the car back to the mechanic, he pointed that there should have been a leak and vacuum the sytem to repair it. Howerver, we found the same amount of refrigerant that he put in the sytem the first time. Meaning that there was not a lost of Freon at that time. He vacuumed the system and took care of a little hole on a hose (Based on what he told me) and then recharged the system back. My AC was doing 55-58 degrees F at the center AC vent. I thought that the system could have done better but it was a lot better than before. I got out of the shop. I drove the car for about 30 minutes and the AC was poorly working again. I used turned off and tuned back on in a little while and the AC used to turn a little better and became warm again.... I do not know.....

Reaccion

Since I did not know how hard it could be to find this A/C tape, I tried to re-use the one on my car. The job was a little crappy but it was not that bad neither. It is some what well covered...

Reaccion

Guys, I was checking online and I noticed that there is a expansion valve only for Matsushita AC compressor. I installed the regular one... Would this make a difference?

Reaccion

AS of now, the temperature here is around 95 degrees. I took the car to the especialist again today (07/07/2012). The guy turned the AC and it was normally cold. He said that there was nothing to fix. I told him that when the I drive the car for some time, the AC will get warm. He asked me that whenever this happends to open the hood and check if the fans are on on the radiator.

sstupid

Well that looks fun to get to.

sstupid

OP, we need to hook up a gauge set to your system. When the motor isn't running, both low and high should be around 125 psi. With the car running and the A/C on you should be about 20-30 psi on the low side and about 200-300 psi on the high side, at around 85 degrees ambient. Your compressor should kick on when the low side dips down to 20 psi, then back off when it goes up to 40-50 psi or so. If your high side is sort of even with the low side, you have a leak. If the high side is really high and the low is low, then you have a blockage, which is usually the expansion valve.

Oil is a pain. Even the professionals don't seem to know how much to add. They just go from experience on what part replacements require what amount of oil. They're just guessing as well. There is no way to measure the amount of oil in the system, so it's easier to just flush the lines/evaporator, and replace the expansion valve, compressor, and dryer, then add the book-amount of oil. Because you have already added oil in and already replaced the compressor and dryer, which can't be evacuated, you're kind of at a guessing game right now.

Reaccion

I think that my mechanic does not know how to solve my problem. He just wants to get rid of me. He explained to me a couple non-sense stuff and asked to use the AC the way it was. He told me that the AC system is properly working. He told me that my engine is "Overheating" making the computer shut off the compressor. He told me that if there is something wrong with my car, the problem should be related with my cooling system and not my AC.... @#@#%$%&(&*)&()&*(

Reaccion

Like an hour ago I checked the AC. I checked and cleaned all the relay connections. I also checked and both fans are properly working. I ran the car for a couple minutes. When the AC started going warm, I stopped and checked under the hood and both fans were running as well..... I am totally lost!!!!!

sumdewd

Next time it gets warm, pop the hood and see if the compressor clutch hub is spinning with the A/C button and fan on. It's the plate with 3 little cylinder shaped things on the end of the compressor where the belt is. If it isn't, you'll need to adjust clutch gap. If everything else checks out, this very well could be your problem.

Reaccion

Yes, I actually checked it already. The AC compressor clutch hub was engaged with the AC poorly working even though the low pressure line is very, very cold.

I was thinking that there was probably a lot oil in the lines already plus I added 8oz more to the compressor. Maybe my AC system is too full of PAG oil! If that would have been the case, How would I vacuum the oil out of the system??