i am having the same exact problems you are. i have brought it back several times. first they told me that it was normal for a 4 cylinder, although it certainly was not like this when the car was new. next they found a bad ignition wire and then they played around with the motor mounts. it does not do it all the time, so maybe they did not get the right feel. i think it is definitely one of the sensors but it is also weird that the slightest elec. surge can throw this car out of whack. must be a bad design. i am going to try one more time and if i can not get it fixed, then i am switching to Honda. i am out of patience.