2000 E320 Starts, Runs for 1-2 Sec then Stalls

[Lance Allison]

2000 E320 90k miles.

A few times now, after sitting a short time, the car will start, run long enough to show oil pressure/tach/fuel level, then stalls. At most it will run 2-3 seconds.

Every time this occurred, repeated attempts at starting was eventually successful. Generally after 5-8 start/stall/restart attempts it stayed running and would be fine for a week or two.

Fuel pressure is normal at the rail and there are no codes, stored or current.
No check engine or security messages.
Swapping keys during one of these episodes made no difference.

I've got the scanner connected to capture any strange readings in live data, but so far I've got nothing.

Any ideas will be greatly appreciated.