I fixed the problem. Thanks aerobod for the link. Once I removed the washer bottle I popped out the filter and a LOT of gunge came out. Cleaned the filter which was covered in this stuff, and rinsed through some alcohol. Works fine now. For those wondering, or those stumbled here this is the steps I took:
This isn't hard but it did invole a lot of swearing because my water bottle was full and quite heavy. You can't syphon water out of it because after the inlet there is a plastic piece blocking your tube from entering. Also it's different to the 3 series guide.
1.) Remove front wheel with 17mm deep socket.
2.) Remove inner wheel arch. This is held on by: 8mm, 10mm, and T30 screws, and 3 pop rivets which you need to replace (30 cents each). The plastic pop rivets are removed by using a small jewlers screwdriver or a pin by pushing the middle in.
3.) Remove the one 10mm nut securing the washer bottle.
4.) Pull the washer bottle down from where the 10mm nut is. You need to seperate the bottle from the inlet pipe. There is a plastic lug shaped like an L at the base of the bottle. Once you rotate the bottle 30 degrees or so clockwise you can then lift the bottle directly upwards and back a touch and it will pop out it's housing.
5.) Carefully slide bottle towards front of car. Removing the pump is easy just pull out and up.
6.) Torque the lug nuts to 103 ft/lbs, one source was 101, the other 105, another 103. I think anything over 100 is enough but do your own research on that.
Never use Rain-X additive, that stuff is pure garbage.
P.S. I'm not a mechanic, you are responsible if you follow my crappy 'guide'
