Working on a 78 450SL that runs good most of the time. Last week it stalled while driving and then would not start. After sitting for 1/2 hour it started and ran fine. The car stalled again the next day while ideling in the driveway. While it was in this condition I checked for spark at the plugs and there was none. Again after sitting it started and ran fine. I don't smell fuel like it is flooding, it is not overheating. I visually inspected the coil and ballast resistors and the blue bracket resistor is cracked in the ceramic from one end to the other, could that be the problem ?

I had Circuit City install a new radio CD player about 2 weeks ago.