do I use any sealant when replacing valve cover gasket on 2004 forenza

check your torque, keep it about 84 to 89 inch pounds. don't over tighten. If it leaks, install again. You should apply a small amount of sealant at points where a change in surface, where a dip or the ends of the cams. Sometimes may help to put a small amount at a few points on the gasket to help keep ii in place when placing the valve cover.