Oil Catch Can Question...

Yuck again.

There is nothing that arrives in the catch can that is needed to be returned to the engine. Good riddance to it all. Think of it as an ongoing oil change where you are culling the most disgusting stuff from the engine and replacing it with your favorite brand of oil instead, like a tranfusion of good blood for diseased old blood a very small portion at a time.

Geez, I'm selling myself on catch cans ever more.

 

I would never go 8-10k miles with any type of oil. It will be so full of harmful particulates chemicals it can damage the engine.
Oil is cheap and is good insurance to prevent damage with 4-5 K changes.

 

I have catch cans on my gtdi engines, but see no reason with port injection, IMHO.