Air conditioner compressor

Hope you are NOT charging it with Freon (R12) - the A/C system in a 1999 vehicle runs on R134a. With all due respect, it seems that you may be much better off taking your vehicle to a professional for proper diagnosis and repair.

Fortunately, the connectors are really hard to mix and match to put R-12 in a 134 system and vice versa. Can be done, but it's a nightmare of various adapters.

One cannot properly charge a R-143a system without a gage set. If you put too much R-143a in the system; the air conditioning performance will degrade.