I have a 1995 Nissan Altima with a 2.4L engine. The vehicle was at a traffic light when it just cut off and would not restart. I tested the firing of the vehicle and found out that the vehicle was not firing through the coil. I replaced the coil and the car is still doing the samething. It turns over, but will not start and it's still not firing. So where do I go from here. This problem has only occurred once.