I have ann 03MCS w/climate control. I popped a hole in one of my hoses from the clutch hydraulic line rubbing against it. I replaced the hose, and added freon. The compressor kicks on an off, but ,it is not cooling the passenger compartment. I hear a noise inside, near the drivers foot, well when the car is running. It goes away when I shut off the engine. We put a gauge on the low pressure side. I indicates a proper charge. Any suggestiions?

 

The system SHOULD have been taken to a full vacume to elimante air and moisture, and a new drier added...then a weighted amount of r134a added...freon is not used.
Not bring the system to a vacume usually results in greatly reduced cooling capacity...air is simply not a good thing to use on an ac system...mositure in the air is pretty bad too...tends to freeze. Do you lnow how much oil you lost?

 

Whenever there is leak in AC system, the vacuum has to be drawn for the refrigerant to work as specified. Otherwise due to the change in colligative property with contaminant in the refrigerant, it cannot work as effectively it should. Besides, you can't add much refrigerant if none at all to a system that has been exposed to atmospheric pressure despite the compressor pulling from the low side.

The gauge reads only pressure of the mixed gas in the system, this case the refrigerant and other mixtures of moisture and air. Combined you have correct pressure yet the pressure should have been entirely/mostly from the refrigerant only.

In terms of the knowing how much oil is lost, that is up to anyone's guess. Too many things play into how much oil has been lost.

Most manufacturers do advertise when replacing certain components in the AC system how much oil should be added (per components being replaced).

Anyone care to look this up? I also happened to need this information but BMW TIS does not show this.

 

Thanks for all of your info guys. I have purchased a new dryer and will get the system on a vacuum pump. It happens that a friend has everything we need to get it back in order. Wish me luck!