Cadillac Repair: 1991 Cadillac Sedan deville air conditioning problem, r 12 freon, cadillac sedan deville

Question
My ac is not cold enough on hot days. I do have access to gages. What readings should I look for to determine if the system is fully charged or maybe overcharged?

Answer
Your system uses R-12 freon. Therefore whatever the low side is, the high side will be 5 times greater.

EXAMPLE: compressor running  if LOW side reads 40 lbs the high side will read 200 lbs approx depending upon atmospheric temperature and barometric pressure.