1996 Chrysler Sebring possible vacuum leak, code p0123

I had to change the valve cover gaskets, and the intake manifold gasket, plugs and plug wires. After the car was re asssembled the problem began. At idle it seems to be ok, maybe slightly rough but just barely. When you press down on the gas the vehicle bogs out as if maybe its getting to much air? then it catches itself and revs up. It is now showing a code of p0123 throttle\pedal position sensor/switch a circuit high. It wasnt doing this prior to being torn down to change the gaskets. Please help