94 SL just cut off. no start

My fiancee has a 94 non turbo 3000gt automatic. Most of the day it sounded like a belt going bad. Slight squeel at idle. Just before the car died it had a very slight rattling noise then in a minute or few the car just died. The front cam cover smells burnt...The timing belt was changed 20k ago. It is a distinct burnt smell on the front timing belt cover. Is there a sensor under there? It just cut off, no loud noise or anything. The motor cranks without any unusual noise. Would a cam sensor cause this? If so is it under the cam cover? I do see a wire going under the timing belt cover. I'm not to familiar with the sensors on this car. What about a broken or loose timing belt tensoner?