Okay, so I'm having a problem with my Dad's A/C on his 95 Sedan. It's a D15B7 & I've evacuated, vaccumed, leak tested, & recharged the system all over again twice with the recover all in one machines that I have access to. I just replaced the Compressor & the Reciever Drier. Put required amount of oil in everything, clutch kicks in & A/C is charged up to spec with 1.4 LBs. The problem is that it's not cold at all until about past 4.5K RPM. I put the guages on both High Side & Low Side, & I'm getting 140 on my high, & my low is going so low that it goes past zero into vacuum with the compressor clutch kicked on. I asked a friend, & he said that it could be the expansion valve not functioning properly, but I prefer more input before I replace it..

 

Forgot to say it passed a leak test too.