Hey I could be wrong, but I believe an inoperative Purge valve would yield, atleast, an incorrect purge flow code. You have 3 circuit low codes all centered around the evap system, which would point to a discontinuity in one ore more of the evap solenoid/sensor circuits. I would first inspect all hoses which go between the charcoal canister, and I would also inspect the wires and inspect the electrical connectors aswell. You may have to cut away wire conduit to do this. If a visual inspection of the evap system does not yield results, post back and we'lll help you move forward.
Also, please provide any other information about the car that you can. Why was it only 600?
Above all, good luck