Is it the alternator? The other day i got in my car to go up the street for coffee and it started up just fine, i noticed the radio wouldn't turn off but i didn't think anything of it. when i got to the end of my street and to my first stop the car started shaking back and forth as if i was bleeding in new breaks, i continued to drive and nothing happened as i gained speed, just every time i stopped the car would shake, when i got to the coffee shop i noticed a loud whistling sound coming from the engine on the side of the alternator and i put the car in the park to stop the shaking but the noise still continued. i called my husband to meet me outside so he could see what the car was doing and when i got home i pulled the car up with it still running he opened the door and the inside light started pulsing and so did the head lights, when he shut the door the pulsing stopped. my husband thinks its the alternator or the tension belt. i have a 2002 nissian altima 2.5 .. i have limited funds and need to order a part soon because no place around me carries the alternator or the tension belt and i fear the cars gonna go if i wait to long, i have one car and a 10 mile drive to and from work every single day. i have no check engine lights on and the car ran completely smooth that morning . the alternator is located behind the wheel in my car and my husband doesn't know how to pull off the tensioner belt to get the alternator tested . has anyone else heard of this problem or knows any ways to test what is going on. thank you