Today my A/C condenser sprang a leak and the A/C system lost it's charge.... blowing hot air. I found oil on the radiator grill after the leak happened. Assuming I can find the leak and repair it, or replace the condenser as needed, what is the process for recharging the system? Is there a separate application of freon and oil required, or do most a/c coolants include the oil component? Does anyone know the proper pressure the system should hold once it's recharged properly?

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Todd
2002 E320 4Matic
1998 E320 4Matic Wagon
1992 300E