Finished a transmission instal on a 1994 my trans am. 4l60e. Before trans instal car ran and drove only had blown transmission. When to start it today and it cranks and pump comes on but wont start. Checked for spark and appears no spark. Where do i start to diagnose why I suddenly have no spark? I know opispark but only thing touched related to opti was the 4 spark plug wires on the passenger side just to reroute around bracket.