MY 96 ram 1500 3.9L was stalling randomly with no warning, i checked to see if it was a fuel issue by taking out a plug and putting in a spark plug and grounding it by holding it on a metal engine mount. When the truck stalled the spark died immidiatly if it is a fuel issue it will keep sparking a little afterwards. The truck even stalled on the scanner and no codes came up. I replaced the Catalytic Converter, 02 sensors, Idle air control sensor and had recently put in a fuel filter and pump. I was told that it was the immobilizer so i took it in to caa and they checked it out but it wasnt the immobilizer they phoned me back and said that they did a test on the IGNITION COIL and it was faulty so i replaced it and there has been no problems. It was only $159.