AC Problems - Low Pressure 93 90q w/ 134A

[Robert Bauer]

My in-laws and I both drive 93 90q's.  They don't have any AC right now.  I
have the earlier model with R12, they have 134a.  I tested the pressure with
the system off and got 100psi.  Started the car went to max AC and got
125psi.  I referenced the Bentley and it indicated something like 280psi is
what it should be.

I know that the evaporators go out on these cars.  But because I do have
some increase in pressure, can I assume it's good.  Has anyone experienced a
leak that was pressure based?

How does one recharge a system with only a high pressure port?

Any advise before they have to take it in would be appreciated.

TIA,

Robert Bauer
93 90q