Muriatic acid and a garden hose. A pressure washer can actually make the efflorescence worse by pushing more moisture into the brick. We always use muriatic acid diluted from 4 parts water 1 part acid to 2 parts water 1 part acid. You could also check into Prosoco restoration products. I know they sell an efflorescence remover.
__________________
Serving Maryland & Delaware with Professional Roof & Exterior Cleaning