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Discussion Starter #1
Two days ago I decided to turn on my AC to make sure it was working plus it was hot that day. The front and rear where blowing warm air with the temps set at 60 degrees max. Today, I decided to purchase the EZ-CHILL from Advanced Autoparts to recharge my system (low-side). The gauge showed that the system was low and I started to fill the system. The compressor clutch did turn on and the system is currently at 45psi (fill zone). Now, the rear vents is blowing cold air but the front vents is still blowing warm air. The dealer installed a new compressor about 3 years ago.

I've researched this problem to possible causes but would rather narrow it down to one possible solution:

1. Blend door - could be faulty. Located under the dash on the passenger side.
2. Some kind of relay preventing front ac to access cold mode?
3. Freon (R134a) still too low - Currently at 45psi but read that is should be at 55psi.
4. Bad compressor - I'm ruling this out since the compressor is maintaining the cold air in the rear vents, thus its working.


Any help is appreciated.. :great:
 

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Orifice tube for the front could be clogged.... That would explain why the rear is cold but the front is not...
 

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Discussion Starter #3
I added another EZ-CHILL can when I got home yesterday. The gauge never went past 45psi when recharging and the front vents where still warm afterwards. This morning I decided to turn on the ac in the front while driving to work and the air was cold but it could be colder. I went and bought another can and will recharge again at lunch time and post my results.
 

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Discussion Starter #4
Update:

At lunch time I pumped another can of EZ-CHILL on the low-side and the front did get colder. Once the can/gauge was connected the reading was around 40psi. I pumped it to 45psi and then emptied the whole can which maintained the 45psi reading. Meaning, it didn't matter how much r134a I pumped, the gauge never went over 45psi..

One thing I did notice which has always happen regarding the ac. When the rear ac is turned on only, the air isn't that cold. But when the front ac is turned on, the rear ac is blowing colder air out the vents.
 

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That's because the rear AC by itself can't turn the compressor on... The front AC has to be on for the compressor to turn on.... I still say it sounds like the orifice tube for the front is clogged.....
 

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Discussion Starter #6
Cool.. That what I figured because I could actually feel the compressor come on when the front ac is used only. Why do you think the orifice tube is clogged even when the front ac is now cold?.... I would have to evac the system, replace the tube and then refill it again.. *urrrrrrgg*...

Don't jinkz me.. lol
 

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If you are still finding that this issue has not been resolved, I would recommend contacting your local dealership for a diagnosis. This would allow you to narrow down the issue. Either way, please feel free to keep us updated regarding the fix. Thank you.

Tricia, GM Customer Service.
 

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Discussion Starter #8
Since most freon related systems are closed looped, I'm sure there is a leak somewhere but how big I have no idea. If this recharge lasts me thru the rest of the spring and summer then I think it would be a small leak or maybe it was sealed by the EZ-CHILL. If I need to purchases gauges, dye, and/or evac tools then thats possible since I will be converting a 84' Chevy K10 pickup to r134a down the road. The dealer is a last resort...
 

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Cool.. That what I figured because I could actually feel the compressor come on when the front ac is used only. Why do you think the orifice tube is clogged even when the front ac is now cold?.... I would have to evac the system, replace the tube and then refill it again.. *urrrrrrgg*...

Don't jinkz me.. lol
Because of how much more you had to add to bring it closer to the rear's temp...... If it's fine now I wouldn't bother.... I wouldn't add anything more to the system though until you at least take a look at it....

It does sound like you have a leak somewhere too though...
 

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I wanna say the evap inlet.... but not sure if that's right off the top of my head....
 

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Discussion Starter #12
Just want to give a update:

After two cans of R134a and 3 days later a can of Stop Leak, everything is cool and holding its pressure. We are getting some very humid 95 degree days so the A/C is being used frequently. Its 10:12am and its already 91 degrees outside...
 

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Mine had a similar problem, but I doubt my solution will be yours. After a new compressor, new condenser, new orifice tube, new accumulator, new hard and soft lines...and still cold air in the back, not so cold in the front, I decided to open up the evaporator box and to my amazement I discovered what could easily had been a rats nest!!??!!?? My best deduction tells me that somewhere in my 89 burbs past the ac was down and the box was not sealed allowing tiny creatures of the night to enter. Some idiot decided to simply seal the box back up without opening it to see if everything was clear. When I took out the accumulator it had 70% blockage in the fins..that would explain why it was not getting very cold in the front. I decided to buy a new evaporator as it was only 75.00 via advance auto parts. A/C is blowing cold now. The rear air puts a chill on the back of my neck...OH YEAH BABY!!! Good luck with yours!
 
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