55 psi low side sounds too high, assuming your evaporator and fans are working. I would vent some off until you get 40 psi. However, R-134A should be recovered since it is a potent green-house gas (soon to be out-lawed). It also smells like ---- (how would I know?), though I heard it is used in Dust-Off cans. If you still can't get it to work, try Duracool or Enviro-Safe, hydrocarbons that work much better and have no environmental issues, but are flammable (so is R-134A).