A/C Pressures - 1993 Town & Country Van - ADVICE Please

Greetings;

I have a 1993 T&C with dual air. I'm charging the A/C and would
like to know the approximate pressures for full charge. It uses
R-134a (factory). Right now at 75 degrees F. ambient I am getting
about 25psi low and 175 psi high at idle. Does this look OK?

Also, I am having an annoying intermittent problem with the A/C
compressor. Sometimes I will set activate the A/C button on the
dash but the A/C compressor will not come on for about 2 minutes.
Usually the radiator fan does not come on right away either. I
checked as many sensors as possible but no improvement.

I am pretty sure it is not low R-134a because the pressures seem
just about right and when the A/C turns on it gets delightfully
cold. Must be something electrical. I don't want to spend the $$$
yet to get a code scan. Any suggestions?

Finally - I don't know what type of oil is in the system. Could be
PAG and could be ester oil. System proabaly needs some oil. All I can
find is ester oil. Is this compatible with PAG, in case PAG was already
in the system?

Gary Jablonski
Atlanta (Hot and humid)