Washer bottle vacuum

[AndyStripes]

Hi folks,
My washer bottle has some sort of air trap or vacuum. The jets get weaker the longer they're used, and I managed to capture nearly 2 litres from the jets but could only pour a quarter of it back into the bottle until it was full?! I've removed the wheel arch hoping to find an air intake nipple/valve or something, but I'm not getting anywhere. Is there such a thing and how would I find or access it please? Cheers.

 

[Fluff34567]

What happens when you leave the cap open and use the washer system? If all ok put a 1mm hole in the cap

 

[t6_tom]

I was having problems filling the washer bottle. It kept overfilling when I knew it wasn't full. Filling it up really slowly seems to have helped.