My oem valve on my B20 wasn't working and I had to switch it out quickly with a Purolator one from the auto parts shop. Since then, my car has been having idle issues, low idle, stalling at idle. Could the valve be the issue?

 

A pcv valve is calibrated to adjust/respond to different vacuum/atmospheric conditions, there is no standard way to calibrate them so yes it could be a possible source to your problem, especially since it started happening right after you put one in.
I would also check the iacv.

 

ive been using one for a while, and i dont think it has anything to do with that, however, i put a Different PCV valve, from a different car which looked the same, this messed things up big time, i guess the spring and shape is different, but im probably wrong, because all it is, is a check valve, im going to make my own and let you know if its any different

 

I changed out my PCV valve tonight for an OEM one and my Idle is back to normal!!! nor more after market parts for me.

 

you mean the one from honda dealership? or the oem type from checker or something?