How would a pro approach repairing an ac with no history on the vehicle & no pressure in the system . I am prepared to pull a vacuum & repair leaks if found . What I can’t find is the correct approach to adding or not adding refrigerant oil to the system . There seems to be no way to determine how much if any oil is in the system & not enough oil is bad & too much oil is bad .
I think your question has stumped the chumps. Not sure about oil in the system but high and low side pressure would be a start.
The system needs to be drained of oil and flushed, for starters.
Pardon my ignorance, but when why and where is oil introduced into an ac system.
There’s no reason disassemble and flush the system unless the compressor grenaded internally.
You repair the leaks, and then recharge the system with a refrigerant that includes a couple of ounces of oil.
With an unknown history on and 11-year-old car with an unknown number leaks and sources of contamination, wouldn’t a clean slate make sense? You would certainly want to have the proper amount of oil.
Oil is in the AC system to prevent the compressor from burning up.
The oil is introduced either when the system is disassembled, or when recharging the system with refrigerant.
On an 11 year old car, I wouldn’t go through the trouble and money to basically rebuild the AC system.
Unless the leak was catastrophic, very little oil was lost from the system.