My general observations are as followed. 1) Vibrations are felt only when car is stopped and idling. It is irrespective of whether the car is in neutral or in gear with clutch pressed. 2) Vibrations become amplified when the engine cooling fan switches on. 3) Vibrations are less perceivable when the car is rolling. 4) On careful observation under the hood at different times, I have noticed that the vibrations persist from the starting of the engine. I could feel engine vibrating at several locations and visibly felt through shaking MPFI (multi point fuel injection) attachment.