Originally Posted by vstech

the specs should be on a sticker on the front of the car, but they will tell you the total charge, not how much you need to top off what is already in there.
listen to the advice you are getting. the FIRST thing to do if it's not cooling adequately is clean the condenser and clear any and all debris from the fins.
NEXT you verify the aux fan is engaging at it's setpoint,
THEN and ONLY THEN should you worry about adding in refrigerant.
also, IF you find that after this is done, refrigerant is needed, you will also require additional mineral oil be added. When freon leaks out, it takes a percentage of oil out with it.