Skip, I went through something like this with my 99 E300 at about 40K miles. The dealer mis-diagnosed my cold startup problem and replaced all the injectors. When that didn't fix it, I took the car back in and they replaced all the glow plugs. That fixed the miss, but there was still a bad nailing in one of the cylinders for several hundred miles. Turns out one of the injectors was bad out of the box. Of course, the dealer always expects good parts so they don't test them first. So if the glow plugs test good, you may want to have another look at the injectors.

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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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