Is it when the car is stationary or moving I wound put my hands on the running engine to feel if the vibration is the same but I would put it down to the upper torque mount or lower engine mount rock the engine if there is play retighten the mounts so they are pulling against each other and are resting on the rubber the only other thing would be vibration from the belts but the logic is the steering and engine have no physical connection so its down to harmonics most likely the crank pulley or component firing the engine crank sensor, cam sensor, ignition and injectors they may not have failed but lost performance
