PCV System
 

Hi guys,

Instead of changing the PCV system, can I simply disconnect the lines or let the oil dip stick bit open to let the pressure out? is there any harmful effect on over all performance of the engine ?

Or I have to change the whole system and spend 300 USD :(

No. It's a "Positive Crankcase Ventilation" system. It is designed to help the engine compression chambers work properly. Taking it apart can cause motor damage.

That will relieve the pressure, but sometimes it can cause air to be drawn in and set codes for the MAF and fuel trim.

Just replace the oil catch tank.