The tutorial video above shows you how to replace the PCV valve on an Infiniti G35. You can find this PCV replacement part over on Amazon for around $23.00 plus shipping.
The product description states: OES Genuine PCV Valve – Nissan no longer includes o-ring #11812-6N200 with this valve; please order separately if needed; 2003-2007 Infiniti FX35; 2003 Infiniti G35, Coupe; 2003 Infiniti G35, Sedan; 2004 Infiniti G35, AWD; 2004 Infiniti G35, RWD; 2005-200