Problems with ac holding charge on 2002 Ford Explorer sport 4.0

I have been working on my wife's 2002
Ford Explorer sport 4.0 liter and got it
running nice and smooth again . Last thing
to do was add a little refrigerant for the
summer as we do every year as it has a
slow leak obviously. Before I added
anything the compressor was engaging
and disengaging every 5-10 seconds. Then
I added r134a and believe I overfilled it
because the compressor stopped
engaging completely ( after adding 1 1/2
cans) a few days later I went back and was
getting low pressure readings on low side
again so I figured I would try and add some
more just not as much as last time. I pulled
both pressure sensors and checked for
corrosion and there was a little inside the
connector on the low side. Sprayed with
electronic cleaner, let dry, and reattached.
Now after adding almost one can of r134a
the clutch will engage again ( on and off
like before) but I noticed there is air leaking
from behind the compressor but in front of
the pressure sensor/ valve . the air isn't
cold as it hasn't made it to compressor yet
but The hole its leaking from appears to be
part of the system like a high pressure
release valve or something. Needless to
say after a day or so the system is empty
again and even during that time I'm not
getting any cold air. Was hoping someone
could shed some light on what's possibly
going on. Thank you in advance for your
help.