That IS the pcv valve, and yes you replace it when it gets clogged and doesn't open/seal properly. It just pulls right out, the rubber gromet it sticks into is replaceable also, so that it is in there snug. Replace it someday and add an oil filter/separator.
Most likely not your problem.
***Replace that fuel filter
, perform a Seafoam cleaning through pcv line or other vacuum line. Add 1 can of Techron to gas tank to help eliminate options or confusion for now.
Check for cracked vacuum lines bundled around the EGR, firewall. The EGR pressure differential switch has vacuum lines to check also.
Mas Airflow Sensor (MAF) should be cleaned but ONLY with MAF spray cleaner, nothing else. Its located on your air intake close to air filter.