I know it's a different year but my 2002 Ram 1500 with 360/Auto use to do the same thing. Would ramdomly start misfiring/popping thru the intake while driving. Almost like it was running on 6 or 7 cylinders. Then it would return to normal like nothing ever happened. The check engine light would come on but would be gone bu the time I got to the dealer. After several trips to the dealer they finally found the problem. It was a sensor located on the rear axle!? Go figure Been fine ever since though!