I just bought a new 2004 Honda Accord V6 and notice that within 3-5 seconds of starting the car, while in an idling position, a vibration occurs in the floor board just under my feet (behind the pedals). It only happens for about one second and then it is gone. It sounds like when popup headlights pop up, but obviously this car doesn't have popup headlights. Then, when I move the car, forward or reverse, the same small vibration comes from the front left wheel and is only there for about one second. Is this normal? I thought it could be the charging of the breaking system or the air conditioning compressor, but am not an expert by any means.

 

sounds similar to the ABS unit priming up, or whatever the heck it does. My car does it for about a second soon after I put the car in gear.

you can always take it to the service department of the dealership you got it from to double check for you, since obviously your car is under warranty...

 

The front and rear engine mounts are electronically controlled, to prevent
vibration once the vehicle is warmed up.
However there is a bulletin on excessive vibration due to a lack
of engine mount dampening. Get it looked at to see if you are
experiencing something unusual.