Hey guys i don't really see much info here so I figure let's get a good thread going for new members that aren't totally aware of CCs while i ask some questions i have. To start ill just do a quick CC run down. As your engine rotates it creates pressure in the crankcase behind the pistons from blow by and this pressure has to go somewhere, engine manufacturers decided the best way to deal with it was to let the pressure vent up through the heads and out the covers(original through crancase seals) In doing this they release gases and oil into the atmosphere, and mostly onto the highway. In order to combat this they decided to recirculate said air oil and gases back into the intake where they would be taken into the engine and burned off. However, this means everything between that recirculation line and your pistons is gonna slowly get coated with oil which will then bake on into carbon and cause you problems. Now over the life of a car most people won't have problems with this, however with high performance cars you tend to have more oil circulating and more buildup. The easy way to combat this is a catch can. It goes in line between your PCV where that pressure is released from the crank and wherever it goes back into the intake (usually after the throttle body). It has baffles in it to catch the fluids in the air and cause them to settle into the can, then the clean air is allowed to recirculate back into your intake and you drain the oil out of your CC every oil change or so depending on your car and the can you choose. Now, anyone that has any issues with what I said please say so and allow me to fix it so this info is all as accurate as possible.