This answer covers 1999-2005 Cadillac Deville, Eldorado & Seville.
2002 Cadillac Seville STS 4.6L SFI DOHC HO 8cyl.
This engine has (2) Crankshaft Position (CKP) Sensors: the Upper sensor is CKP sensor B, and the lower sensor is CKP sensor A (this is included for the OBD-II DTC codes - P0385 references Sensor B = upper CKP sensor, whereas P0335 references the lower CKP sensor (sensor A)).
Both crankshaft position sensors are located in the front of the engine just above the oil filter adapter. To access both CKP sensors, jack up vehicle on the passenger side, remove the oil filter, and the oil filter adapter, including the Engine Oil Pressure (EOP) switch. See illustration.
The ARROW points toward Front of Car.
1. Upper Crankshaft Position Sensor (B).
2. Lower Crankshaft Position Sensor (A)
3. Engine Oil Pressure (EOP) switch
4. Engine Oil Level switch
The Oil Filter is the can-type object below the oil filter adapter, which includes the EOP switch. Recommend: remove oil filter with an oil filter socket/strap wrench, since it's close to the oil pan.