im reading mychilton's book and im reading aobut he PCV system, it says an engine without this is damaged, i know that it returns un burnt fuel and air into the intake manifold, i have an open hose in my engine that went to the stock air filter, anew one is on and the guy left the hose open and not connected to anything, is this the PCV hose and should it be made to re-enter the intake? my truck is a 91 pickup

 

it is the fresh air intake for the PCV system, if its before the airflow meter then its ok to leave it off and put some kind of filter on it, if it was connected after the air flow sensor, then it needs to be reconnected, the computer is calibrated for that air leak, and if you take it off, the engine wont be at its optimum

 

im thinking it was just a fresh air intake. on the old tubing it wasnt connected to em but i dont know if it was integrated with the stock air filter, can it hurt just to drill a whole in my new intake (custom built out of aluminum and ceramic coated) and insert a grommit to make it air tight so its filtered and before the air flow sensor?

*EDIT* ok im looking at the vacuum diagram, its shows it as a resonator, i have no idea what thi sis for but it shows it connecting before the air flow sensor, so could i just tie it inline with my new intake?

 

just make sure you put it where it was originally, if it was before the air flow sensor, put it back before the sensor, and if it was after, put it after, thats all there is to it

 

Just find a small filter that will fit the hose ID. That is what I have seen several people here do. I think one guy is "bike4miles", you can search for his posts or pm him about what he did.