Subaru 2004 Impreza Owner's Manual page 175

Instruments and controls
! Mist (for a single wipe)
For a single wipe of the wipers, pull the lever toward
you. The wipers operate until you release the lever.
3-38
! Washer
To wash the windshield, push the washer button at the
end of the wiper control lever. The washer fluid sprays
until you release the washer button. The wipers oper-
ate while you push the button.