Hi um ive been having trouble with my beautiful black 96 cadillac eldorado.. one day after coming home from the gym. I was getting ready to leave again but my car immediately shut off after ignition.. this has happened before since ive had battery issues but I fixed that so it came as a surprise.. I cranked it once more and boom I heard a loud knock.. cranked it again and nothin.. the car wouldn't stay on.. I replaced the fuel filter checked the fuel pump psi even the ignition switch which a mechanic swore was the issue.. and wanted to charge me $500 with labor and parts for the ignition switc