I bought the car in 2009. A/C wasn't working. In 2010 I went to a home mechanic; he recharged the system with two cans of refrigerant and told me that my A/C compressor was bad. I actually think it wasn't turning at the beginning, and then he told me that those cans had some grease in them. From what I remember after a while (while he was charging the system) the compressor started turning. A/C still didn't work and he told me the compressor was bad. I decided to leave it alone since that part is quite expensive and not worth fixing given the value of my car.
This year, three years later, I was talking to another mechanic and he told me that my A/C wasn't functioning because of the expansion valve. How does he know that without taking a look at my car or doing any kind of tests?
In any case he planted a seed of doubt in my mind that it might not be the compressor. He had two cars similar to mine (stratus and breeze) in his parking lot and he said I could remove the expansion valve if I wanted; he is giving the cars to the scrap yard anyway. He told me it was underneath the dashboard. It took me 5 hours to disassemble the whole thing and get to the expansion valve. Turns out I could have removed it from under the hood in 5 minutes. He was still arguing with me that I'm wrong until I showed to him how it's done. I was really disappointed in his level of expertise and I found a garage that claimed to test A/C for free. They hooked a machine, said there was a leak and said it would cost 150$+tax to recharge it with dye to find the leak. Wow talk about false advertising. I said no thanks, XXXXX XXXXX paying 150$ for this car just to find out the leak and I don't even know how much it would cost to repair it once the problem is found. I said "thank you but I'm going to go" and this is when the mechanic told me that it's probably the big valve (the one close to the radiator). So he knew it before but didn't tell me. I could hear the hissing sound from it after he disconnected his testing equipment (I have very little knowledge in A/C). He wanted to charge me for refill knowing where the leak was coming from so he could then fix it and charge me again for another refill. Anyway once he saw that I was going to leave he said that he was 100% sure about the valve. I asked to replace it. He took out the valve and screwed in a new one (I’m sure the old one was defective because I could blow air through it with my mouth). He charged the system and it was blowing very cold air. I said to myself okay at least it's working now and if there's another leak I have dye in my system to find it. He said that the follow-up inspection would be free if there's another leak and the next recharge would be half price.
My A/C worked perfectly for one day. The next day it wouldn't work. Does this mean my leak is pretty big? When I pushed A/C button on, I would hear a very loud hissing. It seemed to be coming from somewhere underneath the dashboard, but hard to say for sure. In any case it was dark outside so I took out my flashlight and tried to find the leak under the hood. I saw a lot of dye around the expansion valve. It must be leaking? I also saw dye when I removed caps on small and big valves. But I guess this is normal since he charged the system through them?
I have an appointment with him tomorrow morning but I really don't trust him. We will probably be looking for leaks of dye. What questions should I ask him? As I said I have very little understanding in how A/C system works. I'm sure it must be leaking from the expansion valve. I'd rather change it myself than pay a guy who seems to take advantage of me. Is there anything special that I need to know to properly change the valve?
Also the most important questions: is there any way to find out if my leak is in the evaporator or condenser? Is so, I won't even bother. It took me 5 hours to break through to the evaporator on another car and there's no chance in the world I'll be able to put all that back together.
If the guy finds no other leaks than the expansion valve, I'd rather change it myself. I could find somebody to fill my system with refrigerant recharge kit at a lower price. However this mechanic told me it's absolute garbage, it had propane gas in it and it will adversely affect and even break my A/C compressor. Is this true?
To sum it up:
- After being recharged, my A/C worked for one day.
- What could be the hissing noise that appeared on the second day when I would press A/C button and it wouldn’t blow cold air, only normal air.
- What questions should I ask during my appointment? Ex: Specific measurement etc.? I could write them down.
- Is there a way to find out if either the condenser or the evaporator are leaking/defective without taking apart the whole inside of my car?
- Will it hurt my A/C system if I recharge it with a refrigerant kit?
- Based on the fact that my A/C only worked for a day, how big is the leak and what’s the most likely place for it to be?
- Any other suggestions to properly diagnose the problem?
So I went back to the garage and he found that it's leaking from the expansion valve (lots of dye there). We didn't find any other leaks from either the condenser or hoses.
Here's my course of action:
I will change the expansion valve and gasket/seal. This will cost me very little since I think I can do it myself. Then, if I understand correctly, I should go to the garage and ask the guy to apply 28 inches of vacuum for at least 30 minutes?
If it holds, I should recharge the system?
Can you answer my question about the refrigerant kit vs. professional charging?
Also I don't know of a garage that has a sniffer. I think it would be highly specialized and expensive. And I already paid for the dye.
There is no dye seen anywhere except the expansion valve. If I change the valve and it still leaks, wouldn't it be correct to assume that the leak is coming from the evaporator? Are there any components of the A/C system that can leak without being able to be detected with dye, except for the evaporator?
As for the noise I described that appeared when I pressed the A/C button on the second day when the A/C stopped working, does is give you any clue if it's more likely to be leaking from the expansion valve or the evaporator? Or from anywhere else for that matter? Does that sound mean anything at all? If I change the expansion valve, would you recommend also changing the receiver/dried?
I heard that is you open the system, ex. when changing the expansion valve, moisture ca get inside of the system and it will lead to problems, especially for the evaporator. I heard that you have to suck out the moisture from the system afterwards. If this what happens when I apply 28 inches of vacuum for 30 minutes, or is there something else I should do to remove the moisture?
I replaced the expansion valve, o-rings, spring rings and the receiver/drier. It took me 3 hours because I had a few complications and I had to redo it. (At first I installed rings that were too big and it wouldn't fit). It was an extremely hot and humid day (40 degrees). I heard that it's bad when the valve and receiver/drier are exposed to humid air especially for long periods of time. I wonder if this will be a problem in the long run? I went to another specialist after that to vacuum and recharge my system. I think he held the vacuum for around 20 minutes and 20 inches. He said 28 is impossible and that his machine can only go to around 20. How problematic is this for me? When he charged the system, from what I remember one gauge was showing aroung 30 and another 250-350. It's been working fine for the last 3 days since I recharged it. (I must have repaired something for sure!) Now I'm wondering do I have to add A/C oil anywhere in the system? I bought a can just to lube the o-rings and expansion valve gasket. Should I add the rest somewhere or I can throw it away? Also he said that sniffers are very inaccurate, even expensive ones, since the molecules are too small or something like this. He said they worked great on R12.
Thank you. It's crazy those people are all over the place, make mistakes all the time and try to screw you over lol. The surprising fact is that they don't go out of business. Yes I'm glad it's working, finally after 4 years!