Several possiblities here. My mechanic friend had a C240 giving the same CAN to transmission communication error, symptom was no throttle responce on large throttle opening. Eventually cured that one by replacing the bad mass air flow sensor, although it never showed up on the code scans.

Bad crank positions sensor means no spark and no fuel injected, and the failure will likely be heat related (works cold, fails hot). I'd replace it just for "comfort" as it's not expensive. It can also work fairly well at running speed where the engine can "coast" a bit before it works again and cause the engine to quit and refuse to restart because the flywheel speed is to slow to trigger the sensor correctly.

You may also have some fuel pump problems or clogged filter. A pump drawing too much current will fry the MAS relay repeatedly, so I'd get the current draw on the pumps checked rather than toss relays in there, it gets costly.

Peter

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1972 220D ?? miles
1988 300E 200,012
1987 300D Turbo killed 9/25/07, 275,000 miles
1985 Volvo 740 GLE Turobodiesel 218,000
1972 280 SE 4.5 165, 000 - It runs!