Not to argue what you guys have already said, but this may be a factor. I think you're all talking about 616/617 engines that have this problem. And on those engines the glow plugs turn off as soon as you start the engine. Mercedes changed that on the newer ones, I think they started with with 603. They have a circuit that keeps the glow plugs on for a while after engine start. Solves the stumbling problem, but we end up with shorter glow plug life.

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Rick Miley
2014 Tesla Model S
2018 Tesla Model 3
2017 Nissan LEAF
Former MB: 99 E300, 86 190E 2.3, 87 300E, 80 240D, 82 204D Euro
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