[Amaya]

Oh, and you shouldn't need to add refrigerant oil as most of that usually stays in the compressor where it's needed (unless the manual says differently). As far as how much refrigerant to add there will be a sticker somewhere in the engine bay that will give the specifications for the a/c system, it should tell you how much by weight and what type of refrigerant (I think there's a new one that's come out since I stopped working on cars). If you do this yourself make sure you use a vacuum pump before adding the refrigerant. You should let the vacuum pump run for 10-15 minutes, this gets rid of air but more importantly it removes moisture and lets you know the system doesn't have any major leaks instead of wasting refrigerant to find out. Also too much refrigerant negatively affects the cooling ability just as much as too little refrigerant so use the amount they say as a rough guide. Automotive shops usually have a machine that can add and take away the refrigerant and use a thermometer to gauge what level achieves the coldest air temps. If you do this yourself a set of a/c gauges is real handy as the pressures are a pretty accurate way of gauging temperatures and when the system is full. Often times the gauges will not only have pressure measurements but also an approximate temperature reading for a given refrigerant.