My wife has a 07 4.0L 5 speed that is completely stock. Sometimes when it starts up the idle will surge for the first 5-10 minutes of a drive. It will slowly climb to 2500 rpm and drop down to 700ish, then slowly climb back up and do it all over again. Everything drives fine and it always starts. I have cleaned out the throttle body and it seems to help most times, but the problem persists. Has anyone else had this issue? I know OBD1 Fords better than these newer ones. Do these have Idle Air Control Valves or Throttle Position Sensors? Could it be the Mass Air? Thanks!