I have problem with rear wiper wash. The water does not come out fro rear wiper. I have checked the tube and everything else but nothin is loose or any holes present.... One strange thing. When I pul stalk for front windscreen wash, it works very well with water com out of wiper but when I want to use rear wipe wash and turn notch t make water come out of rear wipe, it also does the front windscree as well?? It should not be like that. Can anyone advise me wha shall I do next