have we started with the basics, such as spraying some throttle body choke cleaner in there? it's painfully simple, just remove the air intake tube and spray the cleaner in there, try to get a shop towel and wipe inside there after spraying as best you can ( plenty of youtube videos on this if you'd like ). the thing with our engines is that the throttle body isn't visible to the eye when you take off the intake, unlike other vehicles i've owned and worked on; so just go by feel, use shop rags and plenty of cleaner. don't worry about a tiny bit of smoke, it should be very very light and will go away pretty quickly ( the carb cleaner burns up and goes away very quickly ).
otherwise what would be telling you that you have a bad throttle body? i'm sure there are complete assemblies for it, but it's all a mute point until you try cleaning it first. while you're at it, might as well clean the MAF sensor and check air filter since they are all connected, and may produce similiar symptoms if you are currently having an issue. they sell a 2-pack at auto part stores or amazon, can get two small cans ( 1 throttle body cleaner and 1 MAF cleaner ), so it's a very quick and cheap job to do. should only need about 30-45 minutes if you're not used to taking things off and apart, I recently had my 7 year old daughter do all of the above about a week ago, so don't be afraid to look at videos and just get 'er done.