I've been having this issue very intermittently. It has me a little stumped

Here's what's happening:

1. Insert key
2. Turn to glow position (all typical lights on, except glow light).
3. Attempt to crank (almost no response, no stumbling, etc).

Here's what usually happens:

1. Insert key.
2. Glow.
3. Crank.
4. Car starts (might stumble for a second or two if it's around 40F).

I think I may have a glow plug out because it sometimes stumbles slightly for a few seconds when I start on the the colder mornings, however, this current problem is like the glow plugs aren't even working.

Is this a relay issue? Control issue?

Unfortunately, my DMM is at work...is there anything I can visually check? Corrosion, cracked fuse, etc? Any ideas as to why it'd behave like this?

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1982 240D, sold 9/17/2008
1987 300D TurboW124.133 - 603.960, 722.317 - Smoke Silver Metallic / Medium Red (702/177), acquired 8/15/2009
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