Why would a car vibrate in drive when stopped at a light?

Answer 1

A bit vague his one. When an automatic vehicle is stationary, the engine is "laboured" i.e it is under load, as if you were in a manual car in a high gear but only travelling at 5 MPH. It is common for SOME vibration to occur under these circumstances. It could be that something inside the car has become loose therefor adding to the vibration sound. It might be worth checking you r engine and transmission mountings aswell as any weakness here could result in increased movement under certain circumstances. The easiest way I find to do this is to open the bonnet, and attempt to pull away with the handbrake on both forwards and in reverse, (I would advise that you take care and dont over-do this as something may give way under the torque, just gentle accelerator pressure for a second).Look out for excessive movement of the engine, some movement is normal however. If this draws a blank I would then consider the general engine behaviour, does the car idle OK at a steady RPM? Anything other than the isses I have mentioned may be related to the auto transmission which I believe is a job for a real specialist, I havnt met anyone yet who is really clued up with an auto box (not outside of the specialist/dealers that is).