What the hell is this?

[jezza16v]

The fumes are supposed to be taken back into the engine via the induction system to be burned in the combustion cycle. Taking the breather fumes off to fresh air would help lower the emmissions for the MOT.

[tech1889]

if you think it may be blocked then remove and give it a good ol clean.. just stick a jet wash through its inlet 

[danny_p]

it's a very common mod on tuned engines not to recirculat blow by back into the intake.

its done as std to reduce emissions vented by the engine as it'll reburn all the crap in the blow by but it gunks stuff up with sh!t, makes connections on boost hoses slippy so they pop off easyer and oil vapors encorage detonation, allong with if something goes wrong you cant have a huge surge of oil suddely dump itself in the intake

[tech1889]

thats why on my 1.8t i fitted a catch can.. was much cleaner in the pipes and throttle body afterwards..

[Sam]

This is what came out... ewwww