The throttle position sensor reports throttle angle (butteryfly valve) to the ECU. It does not control idle speed however if it is incorrectly calibrated/positioned it could cause a high idle yes. Do a search on the diagnostic procedures to ensure that it is reporting the correct position while at idle. If it is incorrectly positioned during idle it most likely means it was set incorrectly in the past by someone. 99.9% of the time there is no reason to ever remove or reposition the throttle position sensor.