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AC blowing hot air, hissing sound from right passenger side

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Old Aug 8, 2016 | 01:11 AM
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AC blowing hot air, hissing sound from right passenger side

Hello everyone, thanks in advance for any help on this issue.

My AC has worked flawlessy for a very long time. Today when I started the car and pressed the AC button, I immediately heard a hissing sound coming from the passenger side of the car, from what I could tell, behind the dash somewhere. The AC blows hot air while this is happening. If I turn the ac button off, it still blows hot air but the noise goes away. Turn it on, hissing sound immediately starts up.

Any idea what this might be? Compressor? Leak? I will have to try and fix this myself so the more detail the better if at all possbile.

Thanks so much for the assistance.

Nick
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Old Aug 9, 2016 | 11:09 PM
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it's out of freon you need to recharge it again
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Old Aug 10, 2016 | 08:37 AM
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Thanks! Does low freon level also account for the hissing sound I instantly get when I press the AC button? It is a sound i have never heard before in this car.

Is there a good guide out there anywhere that would help me do this on my own?

Thanks very much!
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Old Aug 10, 2016 | 09:07 AM
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From: tulsa,ok.
https://www.rx7club.com/2nd-generati...gerant-964688/
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Old Aug 10, 2016 | 11:24 AM
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yes the hissing sound is because its very low or has noting of Freon in there
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Old Aug 10, 2016 | 11:39 AM
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Thank you everyone, really appreciate the help!
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Old Aug 10, 2016 | 12:11 PM
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your welcome and good luck with the AC fix
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Old Aug 11, 2016 | 04:30 PM
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Keep in mind if you are leaking refridgerant to find and repair the leak. Don't just recharge it without repairing the reason it's low or empty in the first place.

Also if you do find that the system is low on refridgerant avoid using any refridgerant with stop leak in it as this pretty much ruins your system. Any ac shop will generally not service systems that have been contaminated with stop leak also because it can damage their ac machine.
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Old Aug 21, 2016 | 11:15 AM
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Ok so I bought https://www.amazon.com/gp/product/B0...?ie=UTF8&psc=1 to refill the freon. Anyone able to give me some advice on how to proceed? I don't even see a place to attach this to.

Incredibly grateful for the help, thank you very much!
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Old Aug 21, 2016 | 04:45 PM
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Has you system been converted to R-134a? If it hasn't this will not work.
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Old Aug 21, 2016 | 04:47 PM
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Originally Posted by KansasCityREPU
Has you system been converted to R-134a? If it hasn't this will not work.
I thougt it was the 1993's that were R12 and the 1994's were R-134 from the factory. Is that not correct? Thanks!
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Old Aug 21, 2016 | 07:29 PM
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Just checked and you're good. Didn't see anywhere that listed your year in this thread.

1993 = R12
1994-1995 = R134a

http://www.techchoiceparts.com/refri...pacities/mazda

Last edited by KansasCityREPU; Aug 21, 2016 at 07:32 PM.
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Old Aug 21, 2016 | 07:44 PM
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Originally Posted by KansasCityREPU
Just checked and you're good. Didn't see anywhere that listed your year in this thread.

1993 = R12
1994-1995 = R134a

Mazda Refrigerant and oil capacity charts || TechChoice Parts
Ok cool thanks for checking, I will update my profile with that info.

Now that I have the right stuff, I have two questions.

1. How do I check the current levels and where do I fill it within the engine compartment?

2. someone abovementioned that if it has the seal stuff in it that it is very bad for the car, is that the truth?

Thanks again!
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Old Aug 22, 2016 | 08:55 AM
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Try looking at this manufactures video.

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Old Aug 22, 2016 | 02:35 PM
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I have a 94 fd and the system says r12 so I would check befor mixing refrigerants
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Old Aug 22, 2016 | 04:35 PM
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Don't use the Freon with the leak sealer in it unless you like ruining your stuff. Bring it to a shop and have it repaired properly. The sealer won't seal anything and will only cause you problems.
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Old Aug 22, 2016 | 04:37 PM
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Originally Posted by RX7Zamboni
I have a 94 fd and the system says r12 so I would check befor mixing refrigerants
Where would it say R12 or R134?

Also, with the refridgerant I got, that nozzle wont connect securely to the line in the car, no matter what i do, I cant get a pressure reading or squirt anything in.

OK if you view my profile you will see the PICTURE i uploaded of the AC system in my car. Is it R12?

Thanks

Last edited by rxftw; Aug 22, 2016 at 04:54 PM.
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Old Aug 22, 2016 | 05:38 PM
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roTAR needz fundZ
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If the nozzle won't connect then you have r12 connections, you need to purchase a 134 retrofit kit

And don't be surprised if when you put this bottle in that it doesn't work, or does and not for long. If you had a hissing sound it soulds like you have a leak

The best thing to do would be to get the retrofit kit, and rent a vacuum pump and gauges and make SURE you don't have a leak before pumping a $12-$40 can of 134 in it, or more
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Old Aug 23, 2016 | 12:59 PM
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If u drop the glove box it should have a sticker on the evaporator box saying r-12 or r-134a
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Old Aug 23, 2016 | 01:37 PM
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roTAR needz fundZ
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Originally Posted by RX7Zamboni
If u drop the glove box it should have a sticker on the evaporator box saying r-12 or r-134a
If he bought one of those "a/c pro" cans and it won't fit his low side port, narrows it down that his system is still r12
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