"I don't clearly understand this continuous glowing theory. Do you mean, after the light goes off, wait for up to 45 seconds before cranking? "

Yes, that is what the MB FSM says to do for cold weather.

Bruce , that must have been someone else... because I thought that the timer was for the light..... and that if left in the on position the glow plugs stayed on.... there must be something for turning them off based on some criteria because if they stay on due to carbon build up shorting them out the burn out... but I don't know enough about the system to say what controls that...