this question is directed to all especially the Seniors 
I bought my belta (2006 model, 1000cc) about 2 years ago.. after 1-2 months it developed a
strange vibration. every time when the car stops on a signal & whether i put it to neutral or
just keep the brakes ON (if the signal is about to turn green) the engine used to Give waves
of vibration.. first a slightly bigger one.. then it calms down.. then after 3-4 sec.. may be
another light vibration.. i got it an over the hood check at Toyota walton .. the guy over
there said that he cant do anything about it .. just use it as the way it is.. someone said
get the gear oil replaced & replace plugs.. tuning.. i did all these & though the vibration
gets a bit less right after the tuning .. it does comes back pretty soon..also there was
hardly half a liter of cvt oil in the gear box.. which i replaced with genuine oil(same
advised in this forum )
i discussed this with many mechanics.. but no body gave me a definite answer.most say i have
to live with this as vitz & belta sometimes face this issue & nothing can be done about it..
Now one mechanic has said that it has got something to do with the Hydrolic heads of toyota..
who needs to be adjusted or loosened.. or probably the rubber something around them needs to
be replaced.. but to cut it short.. head need to be opened..which probably will rectify this
issue. or.. i should just live with this 
i dont want to open my engine just on a hunch as otherwise the car is kool without any issue
any suggestions guyz....