91 5.0 TPI, there's a PCV on the driver's side valve cover, and on the passenger side there's just a fitting/hose that goes to the intake with no valve. Question is can i replace the fitting/hose on the passenger side with another PCV or does this unvalved fitting/hose have to be unvalved so the whole PCV system can function???

-Mattie

 

I was under the impression that one valve cover gets a PCV and the other cover has a breather tube so the oil gasses have a place to go.

 

the one on the passenger side is the inlet, the pcv valve on the driver side is the outlet. pcv sucks blowby back into the engine, clean air from the passenger side tube replaces the blowby. if you put a pcv valve on both side, you have defeated the purpose of the pcv system.