Catch Can

[AlexMozza]

I have seen them on some of the MK4-6's and toher cars, but mianly....What are they.

What do they do and are there any performance or running improvements to having them?

[daz veedub]

the function of a catch can is to catch the blow by gases from the crankcase before they are recirculated into the intake (before the turbo)...those gases, mainly oil and water, would otherwise go into the intake manifold and cake the intake valves.

a well worth while mod and ill soon be doin it 

also look good under the bonnet 

[danny_p]

on port injection engines they are mainly a sing that the engine is breathing excessivly and needs new rings.

but on TFSI engines IMO your a tard if you don't fit one.    as fuel isnt injected in the ports it dosent hit the valves and help clean the oil residue from the breathers off them so instead bakes in to rock hard gunk eventualy it starts o cause problems by blocking the port and makeing the valves heavyer it can also affect the ablity of the valves to seal.

so engine output can drop off lots,  seen some TFSI heads that are affully gunked up at sub 50k miles and have lost significant amounts of power from it   were talking 40+ bhp

[Wazzzer]

on port injection engines they are mainly a sing that the engine is breathing excessivly and needs new rings

I fitted mine to stop the throttle housing getting coked up all the time and also to remove the PCV and associated pipes that fail causing boost leaks and rough running

[dragongreengolfgti]

Hi mate i have one fitted now to my ABF and its working a treat its about 1/5th full now over about 2 month period to think of that going back into the engine is not good. The reason i put it on was to stop the unwanted rubbish clogging up the throttle body which is a common problem on the mk3 golf gives you poor running as you will probably know 

pic for you

[AlexMozza]

Looks good