Cadillac Repair: 1991 cad. eldorado a/c, half the story, freon

Question
last year i put r134a in this 91 eldorado.  i didn't change any parts.  It seemed to work for a while. This year it has stopped cooling.  the low pressure side shows about 110. i changed the orfice tube but did not help.  compressor is coming on and seems to run. what do you suppose the problem is? before putting any more 134 in it, do i need to have it evacuated? thanks

Answer
Hi Don, You are only seeing half the story. You need to hook up a gage to the high side also so you can compair pressures with the system off and running. 110psi is alot of pressure and might even be overfilled unless it is a very hot day. DO NOT add anymore freon. Check for codes and try replaceing the a/c relay if it hasn't been done before. Eithor one will cause the compressor not to engage. Bill