My AC wasn't producing cold air. I didn't notice the RPM's change when I turned the AC on, so I tried changing the relay and then the RPM's would change but still no cold air. Then after a while that stopped again too. So I brought it in to a local shop and the guy said the compressor is running and it probably only needs to be recharged. I couldn't wait though so I had to leave and instead of dropping it of there I left it at another station. They just called me to tell me that they charged the system but the problem was the compressor. When I mentioned it was turning on - they said that it's still bad. Then I asked them how did the coolant leak out and his answer that happens when the compressor goes bad. He says I need a new compressor. Somehow this doesn't make a whole lot of sense and I wanted to get some opinions . Any one here an auto-expert that can give any useful advice.
Well... Do you know if the mechanic is reputable? If not, just charge it yourself (assuming the car is newer than 95 you can buy the freon and gauge set included for a lot cheaper than a compressor). Just make sure you understand the ambient temperature outside and check the gauges on tool (A/C on fullblast and car running while doing it). If there is full pressure in the system and compressor sounds like it's working DO NOT add more. If it's low and cycling then add and you'll know quickly if it's compressor or leak etc with how the system responds. I think you can get freon w/ kit for under $15-25. Note I work a lot on cars so (just finished a headgasket, block in profile pic), but on A/C work be careful and don't do something stupid like add freon to a full system etc.
Glad to help, and I know you wouldn't do something stupid with adding/overcharging gauge or something (and didn't mean to sound like a jackass in my post, even though you didn't say that or anything ), but I just want you to be careful and make sure anyone else reading this does so as well, it's an easy way to have things not go well if you ignore the gauges! If you can put gas in your car or a better example.. add air to a tire, this is something that is very simple, so everyone can do it, so don't let some shady mechanic lie to you and say, "yeah, it's the flux capacitor" or something, haha, and again I don't think you would fall for that, but the smart people are the ones that question this stuff (just like you did). I hear daily how the newer cars can't be worked on unless you're a full on mechanic, and while it's true that having some computer skill helps (my background is tech/science etc), it's a load of garbage, (unless we're talking about working on a Tesla...), the only main change the auto industry made other than the computer systems is the freaking specialty sockets/tools you need sometimes (sorry for the bunny trail, it's just something that pisses me off when good people get taken or get good mechanics a bad name, again, I am not sure on the guy that looked at yours, but just something I have seen happen). Anyway, it's really easy to do this charging thing, and at autozone/o'reiley's you should even see a Freon can with a gauge attached (you don't need to go crazy and get mechanic gauges or something unless you're going to tackle replacing the compressor later, and even then since this would be a one time thing you could probably get a loaner set/visit harbor freight (since you have to evac the system/charge it etc, and the procedure will be in Service Manual for your car). On a side note online you can find the exact manuals and specs you need that the actual mechanics use in the shop making something like this a job that anyone could do (w/ the time and tools). Also, I know I mentioned this, but the bottle and/or gauge should have something on there regarding the outside ambient air temp, so like on 70 degree day vs a 105 degree day it will change how the gauge can read etc. there should be something on the bottle regarding the ambient temperature outside (this is what I was referring to), or even the gauge might have it (which is even better). Anyway, just to add, I really prefer to start out easy when I work on cars, and I meant to mention good job starting w/ the relay. So what I am hoping is the system is overly low and adding some will get you going, I have had some cars that had a slow leak and after winter would just add Freon and be good for a year or more, I have had others that were done. If it is the compressor it does make it a bit bigger job but don't get taken by someone until you rule out the easy stuff. Let me know if you have any other questions, A/Cs are not my favorite thing depending on what car, but.. sometimes you get lucky and it is something super easy. This weekend I am tackling a Transmission rebuild on one of my cars, I am pretty sure I can save the transmission, but... won't know till I drop the pan. Good luck, I really hope it is something easy for you! On a side note, if you get good at doing this stuff, you can get just about every tool needed and come out ahead of what a mechanic would charge on just about every repair (I do think A/Cs can be more tricky but just depends)... on my head gasket job for example (granted I have just about every tool available...), I only paid $150 in bolts/gaskets vs the freaking $1500 a mechanic would charge. Sorry for the long trail there, I really like this stuff, and saving money
A leak from dry/worn o-rings ,can be visually traced by oil residue, an eBay cheap Freon detector will help a lot Ac Compressor clutch can be engaged using hot wire to see if work Pressing air pressure switch can indicate if there's enough coolant without gauge
it's possible they needed to charge it to see if it would cool, and see if the compressor was pumping. They could've simply pressured the system to see if there was a leak but would have probably not been able to tell you if the system was working or not, or what wasn't working. So sometimes it's necessary to charge the system to see how it will respond. At least now you know what the problem is and you can go from there.
