How to adjust the throttle control valve of modern car?

When the idle motor, throttle position sensor and other parts are in good condition, first loosen the limit bolt and open the throttle manually, so that your hand will feel a little hairpin, then adjust the adjusting bolt inward and push the throttle slightly, so that the throttle can be slightly opened, that is, as long as you don't feel the hairpin, because the hairpin will accelerate the damage of the engine valve several times.