Rosa is the service engine light on ? If so go to a pep boys or napa auto center and have the codes read. this will give you a really good idea as to what the problem is . Usually when the engine shakes its from a misfire . or It could be the timing is off from a stretched timing belt . The timing belt on these cars should be replaced with regular maintenance around 100,000 miles or every 7 years this will keep the motor running well for years . Dont wait for the timing belt to go or it may be to late for the motor. Hope this helps