I changed the idle air control valve now idle's really high in park 2002 dodge carvan sport 2.4 motor

I have a 2002 dodge carvan sport 2.4 motor I was having problems with it after a week of buying it, I would drive down the highway and it would cut off also would not go when I was giving it gas but would say running had it towed to my house and was told I needed a new computer went to junk yard got used one and It didn't fix the problem. It would start up but would stall right back out so put a brand new Idle Air Control Valve which took care of my stalling problem but no it idles really high like REALLY HIGH in park and when I put it in R or DRIVE it idles down but still a little high can anyone help me.. had a scanner put on and it didn't tell me anything just P1491. and P1495 Thanks!