At approximately 0745 Pacific time, a Cessna 172K lost engine power shortly after takeoff from Tacoma Narrows Airport and was damaged in the ensuing forced landing on a road. The airplane struck an automobile on the road, but no one was injured. The pilot was climbing to 3,000 feet on an IFR flight plan when the engine began to surge. He declared an emergency and was vectored for the ILS approach to runway 17. He broke out of the 400- to 900-foot ceiling about 3.5 miles from the airport but could not see it. He could not hold altitude and elected to land on a road, striking the rear of a car that was traveling in the same direction.