I would suggest changing your plugs if you havent done that in a while. Scotty Kilmer said some hesitation is caused by the fuel running rich which is what you get when the engine is cold. Bad spark plugs dont do well in igniting a rich fuel mixture.
Other than that please make sure your injectors are clean, and do the IAC learning properly. You will need 12.9V and all electricals turned off, including door lamps. Hooking up another idling car like jump starting may solve the 12.9V issue cause Its hard to get that value while the engine is not running.