stinjin

hey guys, im sure this isnt a big problem but im somewhat paranoid to any unordinary occurences with my car.

Jus started surprisingly, after starting the car and idling around 800, or stopping at a light and the rpm's drop to around 800-a honing noise occurs, where a slight vibration goes on and off like on a cycle. i can feel the vibration through the pedals, primarily through the brake pedal. Its almost like having worn rotors and pads when braking...except im applyin no brakes and idling, and no accelerator pressure. Once i start driving around the noise is gone, and like i said as soon as the rpm's drop below 1000, the vibration and noise occurs. i tried listenin to any noises with the hood up, but no noises can really be heard or overcome the noise of the pushrods or belt and pulleys. i can only hear the noise from inside the car, and weirdly enough, only in the drivers side.... :/ although the vibration is in relation to rpm's, it doesnt seem to go in sync with the pistons, per say with the strokes of the motor or exhaust.

maybe a motor mount due to low rpm and rougher idling....brake sytsem like the booster?...maybe a cylinder is goin bad?