It has 6 cylinders and 6 glow plugs. I wonder where I can find my extra cylinder in the om606?

Your best bet is to use an impact gun on a warm engine to get the plugs out. Plus PB blaster.

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Only diesels in this driveway.
2005 E320 CDI 243k Black/Black
2008 Chevy 3500HD Duramax 340k
2004 Chevy 2500HD Duramax 220k