ok so i put my stock valve covers back on due to the Mr. Gasket ones being leaky pieces of garbage. now i have a misfire at idle, and hesitation when i hit the throttle off idle. its an 88 tpi MAF from an 88 iroc camaro, motor ran 100% prior to swapping valve covers out. so i checked my pcv valves and noticed that on the drivers side port where the hose hooks up on the manifold is pushing air, not pulling vacuum. is this normal? what did i do?

 

sounds like a vacuum leak or false air. something you did while swapping covers caused the problem. get a can of carb cleaner and judiciously spray it around the suspect vacuum lines and intake ducting. revs will pick up when you find it. berryman b-12 is a good choice for carb spray.