How much refrigerant did you put in it? The pressure gradient relies on ambient air temp also. Pressures will vary, somthing to do with boyls law or something. The low side seems high but this could be due to over charge. Did the a/c get cold while charging? A lot of times if you know you had a good 30 inch Hg vacum, charge using the low side gauge. Depending on your gauges the R-134 ring should be charged up to 30 psi or degrees F, ignoring the high side due to its relience on temp. If it is not overcharged I would also be inclined to think it was the expansion valve.