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Discussion Starter #1
So today I was heading home from work with the A/C on most of the way and I noticed something very odd when I came to a red light. The cars RPM's got really low. The light turned green and when I took off, the more I gave her gas, the lower my RPM's got to the point that she started to bog down and felt like she was going to die. I heard some loud back fire pops too as I gave it more gas. I let go of the gas, turned off the A/C and it seemed as though everything went back to normal....for the most part. When this was happening, I had the A/C set to about 3 (not full blast but one notch under). But here's where it gets crazy again; since I turned off the A/C, I went ahead and rolled the windows down till I got home (about 30min) but I kept feeling cold air hitting my feet and coming from the defrost vent on the dash. The A/C is off but it's coming out very slow and cold. When I got home I popped the hood and my condenser (the C02 looking thing) was completely frozen with a thick layer of ice as well as the lines coming to and from it. My A/C clutch was also still spinning as though it was on but it was off. I turned off the car and that's when it finally stopped. Can anyone tell me what's going on? Any clue as to what I need to do to fix this? Any help would be great!! Thanks.
 

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The compressor clutch may be locked up. You can remove the belt and try turning the pulley by hand. You can also unplug the compressor itself. It may be low on refrigerant. I am not totally versed on AC systems, so I would probably take it to an AC shop for an evaluation. You can still do your own work if you want to.
 

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Discussion Starter #4
Jayoldschool- I will try this and see what happens.

Fred Kiehl- The clutch is turning and running fine. It's actually new by a few years. What I noticed is that even when I turn the A/C off in the car, the clutch is still spinning as though it's on. I can even still feel the cold air coming out from my feet and defrost vent on the dash. I can't upload a pic for some reason or else I would show you what I'm talking about under the hood.
 

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There is a relay on the relay bracket at the rear right of the engine bay that controls the AC clutch (91-93). A 94-96 relay is in the fuse block. It may be stuck. The other option is the HVAC control module. If the on/off switch is not working it will keep the relay engaged (demand circuit). Check the voltage for the relay coil. If it is always on, it is probably the HVAC control panel.
 

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Discussion Starter #6
Good thought! It crossed my mind that the control that turns on and off the A/C may have gone bad or something. Today I started the car and let the A/C actually run on low for a bit to see what the accumulator would do and after about 5-10 min just sitting in the driveway, the car stalled. My dash lights came on and everything (as far as radio and interior lights stayed on) but the car was dead. It started right back up just fine until the second time when the Pass key Fault light came on and wouldn't let me start her at all for about 5min. I don't know what's going on!
 

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The dash lights always come on when the engine stalls. No big deal.
 

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Discussion Starter #8
Why did it stall though with the A/C on? It happened again when I had the car idealing for about 2min and when I turned the A/C on, boom the car stalled.
 

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The compressor is seizing. Stop turning on the AC. Unplug the connection I told you about. Start planning for a compressor replacement.
 

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Discussion Starter #10
The compressor is turning though. It seems to be working fine as far as I understand it to work. Would not "seizing" mean that the compressor wouldn't move? My concern is that with the A/C on or off, it seems to continue to spin. I unplugged the electrical connectors that's on the side of the accumulator like you said but it didn't seem to do anything. I even opened the fuse box there next to it (up by the firewall) and removed the A/C compressor fuse but again it didn't seem to stop the compressor nor do anything else. I didn't notice this today, I started the car and with the hood up and A/C off, I noticed the accumulator started getting frozen within 2-3min including all the lines. I then turned on the A/C and instead of stalling like it did yesterday, the air came out very cold and the accumulator started to defrost. My compressor is somewhat new. It was installed about 4yrs ago BUT my A/C system only started working since February of this year. I had a few lines that had rusted holes in them so I never had a/C. In February the accumulator, lines and a few other things were replaced and since this everything has been good till now.
 

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Discussion Starter #11
Just to update everyone, I took the car to the shop and jayoldschool you were right even though it makes no sense to me lol. The compressor froze up which was causing everything to freeze and keep the motor on a load. My radiator also has a small crack in it so ill be replacing that today myself. I went ahead and pulled the compressor off and put a bypass pully in so I keep driving. Now I need a new compressor but lucky here in FL we are getting into the cooler time so I can get it later. But I want to say thank you to jayoldschool and Fred Kiehl for your help!
 

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You could have just left the compressor unplugged, and run it. The clutch would allow it to freewheel. Rock Auto has new AC Delco compressors. Make sure you clean the whole system until you get clear liquid out everywhere. Get a new expansion tube as well. You might want to replace the accumulator as a safety factor. You do not want to deal with the "black death". I used a couple cans of carb cleaner because it evaporates quickly, and leaves no residue. You can do the mechanical part, and then take it to an AC shop for the oil and recharge. Just do not hook up the compressor. Let the AC shop do that part.


The parts are a couple hundred dollars plus or minus. The labor is what you are trying to avoid.
 

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when the accumulator ices up that means low refrigerant. so who ever did the job screwed up. you got leaks. how to find leaks ,they should have used some leak detector when they added the compressor oil. then when they charged it and got it running the UV light will reveal the leaks if any.

now back to what is going on . ac on after a little bit the car stalls this maybe due to a defective low pressure cutout switch. if that switch is shorted out the compressor will lock up because it has no oil/refrigerant flow . that switch is there to protect the compressor which maybe why the other compressor crapped out. @Less than 10 psi or so it should open removing power to the compressor clutch coil.

you from FLA. so surprised this was not done properly .. ac is big there.
 

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Discussion Starter #14
Yeah I'm not sure but something tells me the place I took it to was BS. Quoted me $1,367 to replace my radiator, a/c compressor and fill. I just did the radiator myself for less than $200 :/. They took the compressor out and installed the bypass part and told me the compressor was bad and froze up. They gave me the compressor so I'm going to take it somewhere else for a 2nd opinion. The accumulator and a/c manifold hoses are only a year old. Supposedly they checked the compressor an clutch and told me everything looked good last year which is why I didn't replace them.
The crazy thing about it all was that even when I unplugged the accumulator and even pulled the fuse to the A/c compressor, it still kept going and cold air was still coming out! They said that the part that would release and engage the clutch wasn't working which is why it wouldn't shut off.
JCat - the compressor was new by a few years ago but the accumulator and hoses are only a year old. The original manifold hoses had rust on them so the system leaked. I didn't have a/c for about a year. I replaced the accumulator and hoses and had the shop check the compressor to make sure it was good. For the past year everything has been great but all of a sudden the car stalled on me while idling when I turned on the A/c. I start driving home and could feel cold air coming out the top of the dash and the feet so when I got home I popped the hood and the accumulator was frozen and even though the switch inside was turned off, it was still running. I thought it was electrical at first but the shop said the compressor froze up whocj made no sense to me cause when I turned the system on, everything worked properly and cold air came out of the vents and the accumulator defrosted just fine.
 

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sounds like someone changed the wiring or messed with the relay circuits.

ac switch off the compressor should not run / clutch coil no feed. also the clutch should not have any power to it if the refrigerant level is low.[low press switch]

also when an ac compressor fails the system requires a good flushing. condenser and evaporator including all the hoses and replacing the orifice/accumulator/filter dyer .

cleaning the condenser may be difficult some just replace it OR flush it out with a good amount of water solution then blow it all out.

there is a diode at the clutch coil that diode shorts out sometimes effecting the switching components /relays.
 

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Your system needs a professional or you'll risk new parts on a missed problem. If the accumulator is freezing up, you are creating more heat removing potential without removing enough heat. The electrical system, in general, works this closed loop to stop that. A number of issues can cause accumulator freeze up. Constant running compressor, clogged system overall, cabin fan not running, cabin evaporator not getting enough air past it's coils, clogs in same, dust on evaporator, on and on.


Your compressor is doing fine creating a vacuum (obviously). You say your clutch works (spins by hand when the engine is off). If this is true, compressor is likely fine. I vote electrical for now ... clutch is not releasing from your description.


You said cold air is coming out at your feet ... how is that? Don't you set the vents to panel level in FL? Don't miss something odd.
 
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