Im an a/c specialist all i have to say is replace the reciever drier, then either test for leaks via a vac test (done with gauge set) or pressure test (we use a nitrogen rig) dont exceed 220 psi in test situations,if is all clear then vac it down for at LEAST 30 mins one hour optimum, after this suc through 30ml of pag oil either pag 1 or 2 (dependent on compressor being used) and 5ml of flurecent die (to help detect leaks later on) through the low side of the gauge set (has to be done in a certain way) give 5 to 10 mins on the vac pump again, after this lock off high and low side taps on the gauge set then connect the centre line (yellow in colour) to a botle of R134A gas that sitting on a set of scales that have been zeroed make sure the little valve on the centre line is in the off position open up the R134A bottle tap then open the centre line tap. then slowly open the low side tap allowing around 200g (or whatever you can get in there otherwise) of gas in to the system (system is in vacuum no need to bridge wires to fire up compressor) after this lock the low side tap off, start up the car and fire up the a/c system run fan on no.3 fan speed, cold and on recuirculate. After this continue to feed gas into the system via the low side tap (to whatever charge rate is required for this system) let system run for 5 mins or so monitoring high and low side pressures. with both taps locked off switch the car off. make sure gas bottle tap is switched off. slowly undo high and low side taps and wait for pressures to equalise. Disconnect the high side fitting. start car and a/c up again and and suck the last of the gas out of the low side and centre line do this by lifting the revs and getting the low side down as far as possible. undo the low side valve from the a/c sytem and thats pretty much the most of it lol best of luck!!!
