Another glow plug question...

[lietuviai]

Before starting my 300D in the mornings, I sometimes re-glow the glow plugs two or three times before trying to start it. I wait until I hear the loud thunk from the relay when I do this and not at the time when only the GP light goes out. Is there a maximum amount of successive re-glows of the plugs that I can do without harming them? Its just that that's about the only way I can get the car to start well enough that it won't stall out when I pull out the driveway. It won't idle on its own and it misses horribly until it is warmed up enough. I've run diesel purge, checked valve clearances and even changed the GP's without any improvement.