I just replaced all 8 glow plugs. They were probably failing for a lot longer than I realized, as the truck starts quickly and definitely now. But I now notice that the wait light stays on longer (perhaps because it now sees normal rather than excessive voltages?). I generally wait until the voltage meter goes to green before I turn on my lights or start to drive. Not sure if this is necessary.
I also notice now, perhaps 30-45 seconds after the wait light goes out and i crank, that I hear a brief ratcheting/grinding noise under the steering column. The volt meter then jumps up to green. Is this the controller card turning off? It sounds like someone applying a parking brake.
I never do hear the rhythmic clicking of the controller cycling on and off, (perhaps because of an idling engine?).
The truck is certainly starting very well and seems to be behaving well in every other respect. Just don't know what I'm hearing.
Any ideas?