My D4 has been working great lately until about an hour out of Whittier Monday. It shut off and wouldn't kick back on. It did attempt to start up once, but nothing after that. Anyone have any ideas where to start checking? I already checked the fuse and it's good. I didn't install it, so not too familiar with the wiring of it yet. I have a feeling I'm about to get real personal with that thing today. Could it be the glow plug? Fuel pump? Ideas?