I was driving down the highway with heater on and defrost. All of a sudden I hear a pop and my car started bogging down. I exited the highway to get out of danger, it then had a wrench light ( transmission) pop up and when I parked the car on the access road it started smoking a lot. I turned the vehicle off immediately and when I seen smoke coming from under the hood and into the cab of the car. I lifted the hood after seeing fire in the passenger wheel well. And then in the engine block towards the windshield in the middle of the engine. I am a fire fighter and it appeared to me that the fire was being fed by some kind of substance. Fort Worth Fire department showed up and put the fire out and took a report.