basically every AC system has a max amount it is supposed to hold.
this info can be found on a sticker under the hood.
it is usually in pounds and ounces.
unless the car is an import and thenits in grams.
unless you know for sure how much is in the sytem already, you shouldnt be adding alot.
when you take it to a dealer they dont use the little cans.
they either use old school guages or an AC machine.
with the machine they can actually recover everythig out of your system includeing compressor oil.
then they can refill the system with the right amount of oil and Refrigerant
if your AC doesnt work at all, that usually means that the system doesnt have enough refrigerant in it. the compresasor wont kick on if the system is below a certain pressure.
you can add refrigerant with the little cans as long as you dont over do it.
if the car takes 1.5lbs (24oz) dont go and put 30 Oz in it.
get as close as you can with out goign over.
