AoA to all friends.
although this is an year old thread but i want to share my experience to resolve vibration issue. I have personally done the same procedure to get rid off vibration issue in my vitz 2007.
There is a small "LK screw also called allen screw" on throttle body covered with some kind of sealant / silicon type material(as shown in picture). Remove that silicon and tight (clockwise) with Allen Screw driver.(Perform this while engine is switched off). Start the engine and check if problem still exists repeat the action. i resolve it with 2.5 full clock wise rotation. Do not do this on first start of the day, i mean warm up the engine first.
Also remember tight the Allen screw while engine is switched off.
Insha Allah you will be surprised. in case of any query or issue please approach me at my email ID
miclangah@gmail.com