while i driving the sound of radio went off but remained on, lights on radio, cd worked, ac worked just the sound. than air bag light started flashing. car like paused and went than the meter needles went quick right than left. i pulled over turned off and wouldn't start. would take a jump but wouldn't stay running. not sure if electrical along with the alternator which i do need now along with a battery. had alternator replace 1.5 years ago....now someone told me it was tighted to much caused it to go bad is this true also? what is my problem thanks beth