Need some help, don't work on many Saab, this one is a pain. vehicle came in had bad compressor and condenser, replaced both flush out evaporator all lines replaced h block and drier blew out with nitrogen added proper pag oil this was a new ac compressor with new clutch all new seals and gaskets threw out did a balance with oil on comp.,drier condenser vacuum for 1 hour and charge 1lb 12oz with 134a by weight started vehicle turned on ac started to get a little cold low side from start was 30, hi side was 150 with in 3 min the blow off valve let go and low side was 90 psi when it blew, fan working fine sprayed water on condenser to see if gauge would drop , they did not,put a 2nd drier h=block did a second flush all line evaporator, new condenser and lines also sent back compressor 2nd compressor did same thing CAME WITH NEW BLOW OFF VALVE please what am I missing thanks in adv AL.

Al Cloutier
Owner/Technician
A/C Motors
Orange City, Florida, USA