2000 Mercury Sable 24v DOHC 118k, High idle problem

Hello-

My Check engine light is on. Code says manufacturers idle speed control malfunction. I replaced Iac valve and pvc elbow directly under intake and high idle still remains after shutting check engine light off. Is there a specific procedure to reset iac valve on my car? I replaced pcv valve because it was sucked in and vav leak while engine was running. No other codes have have occured except idle speed control code has returned and car idles high. I also have noticed increased stopping distance withe engine idling running /higher. Thanks for your time!