Where is the PCV valve located on a 1998 GMC Jimmy 4.3?
It is on the driver side engine valve cover. Its a small part,
There is a short L shaped (right angle) hose about 1/4 inch in
diameter connected to it. Lift up on the hose and it should
disconnect from the valve cover. the small metal cylinder should
pull right off that hose. Thats your PCV valve.
Note: there is a similar hole on the opposite valve cover, but
that has a larger hose that connects to the intake. You can use
this as a reference to find the PCV valve on the driver side.