Technically, engines always on fire. There is a controlled flame within the combustion chamber/can that will ignite the fuel air mixture passing around the can. Normally, this ignited gas is sent through tubes to the Turbine, which is connector to the compressor section and inlet fan (front of engine) to bring more air in as power increases. Looking at the engine and the images from Pratt and Whitney of what it looks like fully assembled, but before install, the tubes for the gases to go through were forced off, or they are finding ways out of the combustion area.