Hello!

My 240 broke down last night and wouldn't run - story below.

Over the past few weeks, the car has bogged down and hesitated on cold start. It would do this up until the engine warmed up a bit, then everything would be back to normal. This would only happen on some days - generally cold days. Yesterday, the car started behaving that way over the whole drive, even after warming up. And last night it totally gave up - sputtered out and died.

Symptoms (that I could tell - it was freezing rain last night so I couldn't do much but get a tow):
Backfiring (could hear it through the intake a few times)
If the car started, it would run at ~200-300 RPM, very jumpy, until it died a few seconds later.
Oil pressure was good. No coolant in oil, no oil in coolant.
Fuel economy gauge showed a pretty steady increase in manifold pressure until the car died each time.
Fuel pump relay is clicking normally (dropped a spare in, just in case).
Unplugging the AMM or IAC (separately) did nothing.
Distributor cap/rotor are in great shape - no moisture in there
Jumping the right side of fuse 4 to the left side of fuse 6 did nothing - no pump buzz.
Hooked up a spare ECT (just let it sit in the engine bay) - no change

That last note is probably the culprit (main fuel pump) - the pump is original (347,000 miles), but I just wanted to see if anyone had other advice. It seems like the car is running super lean. I probably forgot to add a few things - so ask questions if you've got 'em!