BMW Repair: OBII Code, slow response, o2 sensor

Question
I recently purchased a 2000 528i and I'm getting a check engine light. Using a OTC code reader I get P13917.  I found a code in a Bently manual of PO13917. This is 02 sensor, slow response Bank 1, Sensor 2.  I don't know for a fact that the code I read is the same one. Can you advise me on this? And if so, do you have any idea if a O2 sensor should be replaced, O2 heater? can it cause a slow response?  That Sir are my questions.
Thanks for the assist
Dave, Arlington, TX

Answer
I am not familiar with the codes used by OTC. PO139 is OBD code for 02 sensor, slow response, Bank 1 sensor 2.
Just to be sure, go to an Autozone store and have your car scanned for free. If you get PO139, the sensor involved is the second sensor (called post catalytic converter 02 sensor) of the exhaust pipe connected to cylinders 1 to 3.
Slow response could mean bad heater circuit but BMW sets a different fault code for this which specifies that it is a bad heater circuit. More appropriately, slow response means slow cycling from lean to rich which happens when an 02 sensor is old/defective.
Tino