Cannot rev up in park but runs fine in drive

I have been chasing problems with this car. It would stall at stops and idle high and not come down. All vacuum lines have been replaced. Throttle body cleaned, idle air control valve replaced as well as the fuel filter. After all this the car will have a rough start but will settle into idling while in park. As soon as I touch the gas pedal it will stall. Restart it and let it idle down and put it in gear, there is no hesitation and can drive normally. What am I missing here?