I'm not sure where to post this, but i'm having problems with my RPM. When i'm in park and rev the engine, the RPM get stuck at 1,500 for about five seconds, then settles down. When i'm driving around, the RPM stay at 1,500 without pushing the gas at all. It continues doing this until I come to a complete stop <img border="0" title="" alt="[Confused]" src="images/icons/confused.gif" /> I just recently install H/C also. Thanks in advance!

 

Sounds like a vaccum leak. Check your intake, throttle body, and MAF for any leaks or bad seals. My money is on the intake. Did you install the sensor on the back correctly?