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Discussion Starter · #1 ·
I've noticed recently that the air from the vents with the A/C on is not very cold. Over the weekend, the car was only blowing hot air while idle, and only somewhat cold air while at highway speeds or higher RPMS. I can hear the compressor kick on.

I checked the low side pressure (yes I checked the correct port) and got a reading of 140psi with the compressor on and something like 150 -160 static pressure (compressor off). As long as I'm driving fast the air is cold, but that doesn't really help in stop and go traffic around town. Does anybody have any idea what this all adds up to? At first I thought that perhaps the charge was low, but given the high pressure reading I'm not sure what's going on. Any insight would be appreciated!
 

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Bad compressor.
Even with it almost completely out of freon that it would read extra low not high.
Only other cause is the orifice being defective. Which I havent seen happen in aloooong time but you might check that.
 

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Discussion Starter · #3 ·
So, would that probably account for the clattering noise I hear when you turn on the A/C while the car is stopped? Once the car is moving again the noise goes away.
 

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I've noticed recently that the air from the vents with the A/C on is not very cold. Over the weekend, the car was only blowing hot air while idle, and only somewhat cold air while at highway speeds or higher RPMS. I can hear the compressor kick on.

I checked the low side pressure (yes I checked the correct port) and got a reading of 140psi with the compressor on and something like 150 -160 static pressure (compressor off). As long as I'm driving fast the air is cold, but that doesn't really help in stop and go traffic around town. Does anybody have any idea what this all adds up to? At first I thought that perhaps the charge was low, but given the high pressure reading I'm not sure what's going on. Any insight would be appreciated!
With the pressures you are quoting above at idle the only thing that could cause the low side to be 140 is a weak compressor, If it were overcharged that much to give you a 140 on the high it would not cool at all due to the massive overcharge of r134a.
The compressor is just a pump so as the rpms speed up, the pump turns faster hence it cools at high speed.
 

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Discussion Starter · #5 ·
Thanks for the input everyone. I have ordered new o-rings, a drier and a compressor. I'm going to take it to a local shop to have the system evacuated so I can do the work. I'll take it back to have it vacuumed, leak tested and charged.
 

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Thanks for the input everyone. I have ordered new o-rings, a drier and a compressor. I'm going to take it to a local shop to have the system evacuated so I can do the work. I'll take it back to have it vacuumed, leak tested and charged.
For reference , What brand of compressor was it and what was the cost?
 

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Discussion Starter · #7 ·
I bought a Denso for $295. I did the install yesterday. It was a fairly easy and painless DIY, no harder than the water pump. The bolts for the drier a bit hard to get to, but nothing too bad. I'm taking it to the shop tomorrow to have it recharged.
 
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