an incorrectly adjusted throttle position sensor will also give the same symptoms.u need to check the tps signal voltage with the throttle closed,and if your using the wrong tps this can compound the problem,
as a ball park the sensor should be in the middle of the slots,there are voltages which depend on the sensor used,it should be 0.2v to 0.6v or 4.9v to 5v at throttle closed.someone on here may give a more precise procedure