Thanks by "cracking" the fuel injector lines, do you mean disconnecting them one by one to see if the sound stops?
Oh, and does a bad rod mean an engine replacement? Sorry if thats a dumb question, but I only know enough to work on them if I've had the problem before. If its a new problem then I'm ignorant.

Cracking them only takes loosening the nuts at the injectors by about a 1/2 turn with a 17MM wrench. Some fuel will leak out but it shouldn't spray. The car will run rough momentarily until you tighten the nut back up again.
If its a bad rod bearing, it'll more than likely have damaged the crank. To replace a damaged crank requires tearing down the entire engine. I did that on one engine I have this past Saturday. Most of the rod bearings were gone on this engine. I never heard this engine run but I imagine it sounded much worse than yours before it died. I have a thread about the tear down.
I hope this is not what is wrong with your engine.

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DJ


84 300D Turbodiesel 190K with 4 speed manual sold in 03/2012

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Take a look at the primary fuel filter and see if it has a bunch of air in it.

You could possibly have a clogged fuel filter ( one of the three on the car )
Or an air leak into the fuel system.

If your engine is starved for fuel this kills power and can cause injector nailing.

Thank you
RichC

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When the power of love overcomes the love of power the world will know peace.
Jimi Hendrix

My guess is one of the cam lobs gone caused by the low oil pressure. Probably an exhaust valve causing very high pressure in the associated cylender. The oil pressure could be caused by stoped up drain back holes in the head which explaines the "no oil on the stick, then overfull the next day".

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84 500 SEL (307,xxx miles)