ok so I have a 95 pontiac sunfire ya I kno its old but lately it feels like its shaky when I drive and it seems different when im in park with it on it sounds louder & shaky. I have new everything basically the most recent was a bad ground 4months ago but I fixed it cuz all the lights on my dash would stay on which they dont nemore. Ever since I got the car 3yrs ago the air bag light would come on & off rarely but now it seems like that light also stays on now idk if I should be worried or not also sometimes when im driving I hear like a whistling almost sounding like fire trucks but its low soundin and kinda seems like its comin from the trunk area/muffler area. What do you think it is??