Steve - your car has the second year of the 3.5 603. You may already know that some folk have had problems with these bending rods, especially in the #1 cylinder. The rod bends, the cylinder gets out of round, and insane amount of oil are used. I truly hope this isn't your situation. There is a lot of info about it here if you do a search. The thing I think you have in your favor is that I would expect oil consumption, not leaking. Still, maybe it needs to be ruled out.

Good Luck.

__________________
Tjohn

82 300 SD
77 450 SL (gone)