In a message dated 7/13/99 1:38:07 AM Eastern Daylight Time,
JMSHINOSKY@aol.com writes:

<< I am doing the troubleshooting on my 88 Weekender A/C system for it
 blows warm air. I checked the low pressure line valve but I couldnt find the
 high pressure valve. Does anyone have an idea where will I find the high
 pressure valve? (FYI: This A/C system is converted to R134 by the previous
 owner.) >>
James the high pressure valve should be under the plastic cover on the
driver's side in the opening of the rear hatch.  Remove the cover and it is
right there.  Your affliction sounds like low charge to me.  Check the
pressures and add R-134a and you should be back on line.  You may want to
take the van somewhere for a leak check or add some of that red leak
detecting dye in with your oil so you can see  where the leak is and fix it.
Ken Wilford
Van-Again
John 3:16