The really stoopid thing is that the 155 with the same engine did have the low level warning light and sensor, why the bloody hell didn't the 156 inherit it. Were talking some fuzzylogiz circuit, one sender and a sngle warning lamp.
My 156 ate a conrod and the crank a while ago. I'm the second owner and have done most of the miles on the odometer, and it has NEVER been run low on oil. I used to work for an Alfa dealer so I'm very vary about the oil level
Out of the blue, the bearing on main journal number two went, it being a Selespeed meant that I could not depress the clutch and turn the engine of but I had to wait to get to the hard shoulder of the freeway, before turning of the engine.
What looked like a slightly damaged journal on the crankshaft turned out to be a heavily warped crankshaft, meaning it couldn't be reground.
Alfa Dealers actually do sell reconditioned crankshafts, but from judging the finish of the one I bought, it looked brand spanking new. It came with a complete set of bearings matched to the crankshaft big and small end bearing size, for half the price of a new crankshaft excluding new bearings. This somehow hints to me, that AlfaRomeo is helping out unlucky owners in this way.
It took quite a while to recondition my engine in this way in the driveway, but it was way cheaper than a reconditioned unit
Hope this helps