1992 Eagle Summit wont start

Well the car turns over but wont start and from what I checked it doesn't spark either. I was at a light the car stalled well my girlfriend was driving the car was rolling and she oput it in park while rolling. She tried to start it up it tuns over but no spark I checked the spark and it did not spark. I checked the timing belt and it was fine. The car has a exhaust leak for a while and the car has been back firing and having loss of power the last month. I put some medal on the leak on the exhaust and it help a little but still back fired and loss of power. I did put new spark plugs in and the wires a dist cap were from last year new. What could this be?