The info was right on ! Thank You !, it was the crank sensor but removing broken piece in the block seems impossible. A guy says he has a tool for that . I don't. I tried leaving it in for a five mile gamble but the car stalled and the battery was dead just like that. Removed the new one thinking it was broke but it was'nt. Fished around with thin metal objects and I can get the piece to almost lift but it seems caught. Can I remove the oil pan and pluck it out ? Did I ruin the motor by leaving the other piece in there ? Please help , Thanks , Eric It's a 2.5 1986 Century Buick