Well, I had this same problem in Doom, but there was an option to turn off vsync in the doom menu, which I did and the problem was fixed. (http://www.ocforums.com/showthread....t=6800gt+2001fp)
Now, on Lock ON and IL-2 I have the same problem. I have vysync disabled in the nvidia settings, but have the same problem.
Now, that I think of it. When playing Doom3 if I had it disabled in the nvidia profile, shouldn't it have been disabled in Doom3 even with it set to on? I did not have it as application controlled..
This is driving me crazy. Maybe I'm not changing the setting correctly? I'm at a stand still.