'99 Burb Stalling

HI, MY SUBURBAN, AS WELL AS MY BROTHER'S, IS STALLING OUT. CHECKED ON A PREVIOUS THREAD ON THE SAME PROBLEM WITH A 2001, AND ALTHOUGH WE HAVE JUST ABOUT THE SAME SYMPTOMS, SEVERAL THINGS CROSS MY MIND:
1.- MY BROTHER'S IS A '94, 5.7L V/8 WITH T.B.I., 2x4
2.- MINE IS A '99 WITH VORTEC, ALSO A 5.7L, ALSO 2x4

AND THEN THE QUESTIONS ARISE:
COULD CRANKSHAFT POSITION SENSORS BE CAUSE FOR STALLING ON BOTH VEHICLES?
WHERE IS C.P. SENSOR LOCATED?
CAN IT BE DIAGNOSED WHEN TAKEN OUT?

EVERYTHING ELSE SEEMS OK, ALSO NO TROUBLE CODES DISPLAY. OH, AND NO K&N FILTERS ON THEESE.
THANKS.