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Air conditioning not working

Discussion in 'Terminator Talk' started by TERMINATED97, Jul 15, 2019.

  1. TERMINATED97

    TERMINATED97 Well-Known Member Established Member

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    1. So I bought back my MC cobra from my buddy. When I sold the car in 2015 the AC worked just like it should. My buddy never drove the car and only put 500 miles on it in the last four years. On my way home Saturday, I turned on the AC and its blowing hot air. So here's the issue I'm having. I went to Walmart and bought a recharge car with a gauge on it. I plugged in the gauge today and it went to "full" without me doing anything. I then heard a single clicking noise and the gauge dropped down to zero but then would slowly move back up to full. It did this about five times until I just unplugged the can. I ended up not putting any refrigerant in the car because of what the gauge was doing. I know nothing about AC systems but it almost seemed like it was something with the compressor or something of that nature. Does anyone know anything about this or can lead me in the right direction? Also, I am so happy to be back in my old terminator! Thanks

    Doug
     
  2. decipha

    decipha Active Member Established Member

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    thats perfectly normal whats happening is that when the ac compressor kicks on there is insufficient refrigerant so its sucking down to vacuum. You have a major leak you need to fix that before putting refrigerant in it.

    The ac system is a sealed system. You should never have to add refrigerant if you do then you have a leak.
     
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  3. Revvv

    Revvv Infinity Poster Established Member

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    If the car has sat for a long time, you may be able to add a can of refrigerant sealant to the system. This will condition the seals if that is where the leak is. You can also add in a can of dye to find the leak once the system is full and working properly. A black light should show the source of the leak as the dye seeps out.

    Sent from my [mind] using the svtperformance.com mobile app
     
  4. turbovenom

    turbovenom Member Established Member

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    My f250 ac didn’t work because there wasn’t enough Freon in it but it wouldn’t try pretty sure they have a pressure switch so clutch won’t engage if there isn’t enough refrigerant to save the compressor, anyways it was effin hot I was in a pinch I added more to it thinking I’d fix leak later. It’s been 4 years now and it’s still blowing cold. I’d add it till it says full all the time if it never gets there it might be restricted somewhere causing the low side to hit a lower than intended pressure. If it is and there’s no flow there’s not going to be any cooling going on. If it’s just low you will have fixed. Kinda hard to tell not knowing the high side pressure but it sounds like the compressor is trying I’d spend the small amount on the refrigerant before paying someone to figure it out.
     
  5. decipha

    decipha Active Member Established Member

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    also, that uv dye and leak detection method is pretty archaic usually it just makes a mess and doesnt pin point the leak unless its obvious enough that the dye isnt even needed

    best method is to use a digital refrigerant sniffer Ive found cracks in welds before with them that were undetectable with the dye.
     
  6. Revvv

    Revvv Infinity Poster Established Member

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    This is true. The dye was just the quick, cheap, and easy try.

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  7. turbovenom

    turbovenom Member Established Member

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    This^ but I figured since dude didn’t know ac at all he won’t have one. If ya got a buddy who does that would be best they are incredibly sensitive and can find the smallest leaks. But I’d still give the ole Walmart can a try.
     
  8. *Jay*

    *Jay* Tweeker by trade Established Member

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    You can go to auto zone and use the rent-a-tool to borrow a set of actual AC gauges. I would do that and google how to use them before just throwing a can of anything in.

    Once you ID your issue you can also rent the compressor to pull a vaccum and the proper tool to fill from the freon cans with the gauges on. Only issue is if you have to pull vaccum and you arent empty of freon they dont have the tank to purge into and venting freon to the atmosphere is a big no no.

    Also if you had a leak and currently have no freon you need to replace a few things in addition to finding and fixxing the leak.
     
  9. TERMINATED97

    TERMINATED97 Well-Known Member Established Member

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    Wow, thanks a lot guys! This helps tremendously. I’ll mess with it again this weekend!


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  10. 01blckcobra

    01blckcobra Active Member Established Member

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    Best to take it to a shop that has the equipment. More than likely the o-rings on the compressor dried up / cracked. The system will need serviced, flushed, and recharged. Wouldn't recommend using cans from autozone / ect. The product contains sealer which is not good for the compressor itself. Also, you are putting outside air into the system. Only reason the compressor is saved is because of the pag oil in the system.
     
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  11. ur bittn

    ur bittn By the snake Established Member

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    ^+1
     
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  12. BigFatMatt

    BigFatMatt Ain't never gonna change Established Member

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    When you turn on your AC, does your compressor clutch engage?

    This sounds like an issue I was having. The system was charged and seemed to hold pressure just fine. But mine blew hot air.

    Mine was the low pressure switch. It failed and my clutch wasn't engaging because the switch was mistakenly telling the car the pressure was too low (prevent damage to compressor).

    I knew I had a sufficient charge, so I removed the connector from the low pressure switch and jumped it with a paper clip. Clutch immediately engaged and COLD AIR!!

    I'd do this before taking your car to a shop. 2 minutes, pop your hood, disconnect connector, jump with paper clip. If your clutch engages and you get cold air, replace the $10 switch and you're good to go.
     
  13. Black Gold 380R

    Black Gold 380R Multiple SVT Collector Established Member

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    This first if you can figure out/understand your A/C system.

    This first if you don't understand your A/C system.

    The A/C system in your car is very technical and requires special tools and the ability to follow certain federal regulations (i.e. not just letting Freon/refrigerant evaporate into the atmosphere) in order to properly repair it. Each system requires a certain amount of Freon/refrigerant and a certain type (i.e. R-134a or 1234yf).

    You need to know which type your car uses (03/04 Cobra should be R-134a) and how many ounces of Freon it takes. You need to make sure all your components are working properly (i.e. compressor, condenser, dryer, expansion valve, etc). You need to ensure there are no leaks. Don't assume just because it blows hot it's automatically low Freon/ refrigerant. Could be a bad compressor or faulty expansion valve or clogged condenser, bad pressure switch, etc. Also, over filling the system is just as bad as not enough.

    I'm no expert, but have taken the time to learn how it works and how to properly diagnose problems and how to properly fill the system. I have repaired the A/C systems in my 99 Contour and 06 Ford Five Hundred. I had to purchase a set of A/C manifold gauges, a mini compressor to suck all the air out of the system and create a vacuum and monitor that vacuum to ensure there were no leaks. Then used the manifold gauges to add the Freon/ refrigerant to the system and lastly had a temperature gauge placed in the A/C vent to ensure it was operating at the correct temperature.

    Can be done, but it is not as simple as buying a can, hooking it up to your A/C system and filling it up.
     
  14. 01blckcobra

    01blckcobra Active Member Established Member

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    Wouldn't recommend jumping the low pressure switch before verifying the freon charge is adequate.....
     
  15. BigFatMatt

    BigFatMatt Ain't never gonna change Established Member

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    You must not have read my post.
    There you go son. Sufficient charge FTW.
     
  16. 01blckcobra

    01blckcobra Active Member Established Member

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    Tested with pixie sticks? Some people jump off a bridge and survive also..
     
  17. decipha

    decipha Active Member Established Member

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    in the OP he specifically states the charge dropped to 0 once the compressor kicked o

    its obvious he is low and thus has a leak

    usually 9/10 times the main seal in the compressor is what fails and causes loss of pressure
     
  18. zredfire04

    zredfire04 Active Member Established Member

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    i had to put a new hose/manifold on my 95 gt because the actual hoses were leaking.

    verified with dye BTW.

    what do i know, i only work on refrigeration for a living.
     
  19. CobraBob

    CobraBob Authorized Vendor Premium Member Established Member

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    If it was me, because I know little about A/C systems, I'd opt for just taking it an A/C shop and let them diagnose the actual issue and fix it right the first time. I'd probably just do more harm than good attempting to do it myself.
     
  20. Black Gold 380R

    Black Gold 380R Multiple SVT Collector Established Member

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    Guess that would make you the resident expert and the one most qualified to provide advice and answers.
     

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