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Discussion Starter #1
I picked up my 320 at the dealership after solving a problem with the accelerator not working. I noticed the AC was not keeping the car as cool as I was used to but I chalked it up to extreme temps.
3 days later as it started cooling less it finally stopped cooling altogether.

I bought an AC charger and proceeded to charge but realized the pressure was too high about 150 PSI on low side charge port.

I then read that wasn't necessarily bad if the compressor is off. The compressor will turn off if the refrigerant is low I believe. Compressor and fans do not turn on.

What I find odd is this: If the compressor kicks off when the refrigerant gets low, and when the compressor is off the pressure is too high to even charge with gas? How does one charge it?

This makes no sense to me. Any suggestions?
 

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I picked up my 320 at the dealership after solving a problem with the accelerator not working. I noticed the AC was not keeping the car as cool as I was used to but I chalked it up to extreme temps.
3 days later as it started cooling less it finally stopped cooling altogether.

I bought an AC charger and proceeded to charge but realized the pressure was too high about 150 PSI on low side charge port.

I then read that wasn't necessarily bad if the compressor is off. The compressor will turn off if the refrigerant is low I believe. Compressor and fans do not turn on.

What I find odd is this: If the compressor kicks off when the refrigerant gets low, and when the compressor is off the pressure is too high to even charge with gas? How does one charge it?

This makes no sense to me. Any suggestions?
IN this case you need to vacuum the system and use guages to check for leaks and then re charge the system. If the system holds the vacuum reading then all is ok and not leaking, but if it does not hold a vacuum pressure then you need to search for the leak.

From what you have posted the system does have a leak.
 

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Discussion Starter #3
IN this case you need to vacuum the system and use guages to check for leaks and then re charge the system. If the system holds the vacuum reading then all is ok and not leaking, but if it does not hold a vacuum pressure then you need to search for the leak.

From what you have posted the system does have a leak.
Ok this is what I was thinking and hoping for as a response. I will proceed to see if I can have it vacuumed and charged.

Thanks
 

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Ok the mechanic says the compressor is bad.
I am thinking of buying an aftermarket compressor and letting a local mechanic install it.

Any suggestions? Where to buy a compressor?
 

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Ok the mechanic says the compressor is bad.
I am thinking of buying an aftermarket compressor and letting a local mechanic install it.

Any suggestions? Where to buy a compressor?
For a car this age there should be plenty of second hand units available at your local junk yard, save even more money.
 

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AC not working

There is not enough information here to make a recommendation...In a closed system that is not operating, the R-134 pressure in psi will be close to what the ambient temperature is in degrees f...If the system is properly charged but the car is cold and not running and the ambient air temperature is 75 degrees f, the system pressure will be 79 psi...This tells us that the ambient temperature was well over 110 degrees f at the time you took the pressure reading and the system was not running...This does not necessarily mean that air temperatute was over 100 degrees, it could mean that car and engine were hot...If the engine was running, then the compressor was not engaged, otherwise the pressure would have been pulled down...The suction (low side) pressure should be in the area of 35 psi if the system is working right...It could be that the compressor clutch was not engaged because the fuse is blown...

Some folks like to keep a can of refrigerant in the trunk "just in case"...It can be seen that this is very dangerous because the interior of a parked car on a hot day can reach 150 degrees and the pressure in that thin tin can would be about 250 psi...

Bigblue
 
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