hi there I guess your talking about the oil breather valve?? Mine broke and I ziptied it together till i got my replacement. :$ Not sure if it causes any oil pressure loss, but certainly hasnt caused any problems or damage and this happened 2 months ago. I got my replacement from a Ford garage off a galaxy v6 as I was told you had to buy the pipe it is connected to aswell if purchased from a VW dealer. Anyway here is the Ford part number 7364573 total cost was £24.98 Hope this helps