A/C pressure

2003 PONTIAC MONTANA
72,000 MILES • TURBO
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XJSHEN
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My problem is high side pressure was 70 psi, and low side pressure was 100 psi. when filled with R134 refrigerant after vacuum removed at 30 psi. but this vacuum reached very fast within five minutes. And one can refrigerant was not fully filled into low side since the pressure as high as 100 psi at low side, and high side was only 70 psi and both needles were vibrating, and no more refrigerant can fill into system. I stopped run the car with cooling, and there was no cool air came out both front and rear A/C.
Thanks for your comment and instruction to helps to fix the problem!
Jul 3, 2017 at 4:29 PM
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MHPAUTOS
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It sounds as if the compressor has failed. i would get an A/C tech to double check this first hand and quote any repairs.

This guide can help

https://www.2carpros.com/articles/car-air-conditioner-not-working-or-is-weak

Please run down this guide and report back.
Jul 4, 2017 at 3:30 AM
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XJSHEN
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Yes. You are right. My compressor is leaking.after dealer repair on my coolant out leaking caused multiple problems. Thanks for your comment!
Jul 7, 2017 at 2:19 PM
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MHPAUTOS
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good to know you have found the problem, thank you for using 2carpros
Jul 8, 2017 at 5:32 AM
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XJSHEN
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Hi,
I started to check on my a/c system. I found there was no o-rings on the a/c line inlet/outlet connector to condenser. Is it normal case without O-ring on GM system? I found leaking dye traces on the connectors. Should I put o-rings or not?
Thanks for your instruction and help!
Jul 20, 2017 at 1:59 PM
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STRAILER
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Hello,

Yes install a new o ring and then recheck for leaks. Here are some guides that will help you get the job done.

https://www.2carpros.com/articles/air-conditioner-leak-detection

and

https://www.2carpros.com/articles/replace-air-conditioner-compressor

and

https://www.2carpros.com/articles/re-charge-an-air-conditioner-system

Please let us know what happens.

Cheers, Ken
Jul 21, 2017 at 10:50 AM
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XJSHEN
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Thanks a lot for your help again! I have discharged a/c system completely, and rebuild the system. And I am going to do engine works to fix coolant internal leaking problem. Does intake gasket-engine part works need discharge a/c system while need discharge cooling system. If yes. I do not need to restore my A/C system until finish engine part work. If not, I can restore A/C system before engine works. Thanks for your instruction and help!
Jul 21, 2017 at 12:00 PM
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STRAILER
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Yep, look and see if the intake can be done without removing the compressor if so you can finish the ac work or do it later you will be okay.

Please let us know what happens.

Cheers, Ken
Jul 21, 2017 at 2:45 PM