I would not blindly add R-134a to your system. Youc can very quickly overcharge your system and not know it, which could ruin expensive parts or be quite hazardous. You should have a leak test done and the leak repaired. Otherwise even if you get the correct charge, oil often leaks out as well as refrigerant and you may ruin the compressor from oil starvation. Just my 2 cents, but good luck fixing it.
