whunter, others(?),

Update: a bit of a 'report' from this weekend...

First: Car generally runs great; I'd even call the pickup great for a 30+ yr-old diesel, which needs a valve adjustment...(!)

However, I occasionally get a nearly complete loss of power - I mean a really crippling, slogging-along-at-20mph kind of power loss.

Had to do some highway driving this weekend, so tested things. Problem only really appears at speed, and especially under load - as in climbing a hill. Issue seems to appear more often after car has been running for a while already.

Also, pulled off the gas cap during all this - no change in behavior - does this remove the fuel return system from the diagnostic mix?

As much as I am planning to do the nozzles and lift pump anyway, I'd still like to get to the bottom of this specific symptom - what could be causing?

__________________
'83 300 SD
'05 E320 4Matic
'06 BMW 530 xi
'68 Triumph TR 250 - The only car I ever loved more than the Mercedes; who needs electricity, anyway? - Damn, why did I sell it?!
'59 Jaguar 3.4 'Le Chat Noir' - Damn, why did I sell it?!

It's difficult to make predictions, especially about the future.
- Niels Bohr