Well, I'm finally back in the driver's seat of the E300 after two weeks without it!
The reason it was gone?
We had our diesel mechanic take the head off to replace a stuck glowplug, which had been in there for almost a year. The car was a PITA to start when cold, belching white smoke and eventually, reluctantly, sputtering to life. We intended to have a valve job done as well, but seeing as oil consumption was practically zero (even at 173k)...and how a valve job on a 24-valve head is big $$$$...we decided it was unnecessary.
Last night we decided to leave it outside (temp got to about 45º), and I went to start it this morning. Turned the key right after the GP light went off...and it sprang to life on the first crank!
It settled immediately into a nice, smooth idle, smoother than I've heard from it in a LONG time. I'd say it's loving its like-new compression!
Other than the glowplug R&R, it's received new tires, brake pads, and shocks...winter, here we come!