Motronic Fault Code for e36

["Sean A. O'Rear" <saorear@xxxxxxxxx>]

    I have just recieved a new fault code on my 93 318is.  The code is
1286 - which corrosponds with "knock control test pulse" according to the
FAQ at http://cbsgi1.bu.edu/bmw/new_bmw.html.  What does this mean?  What is
the sensor that picks up this "pulse".  I was wondering if this was due to
some routine maintanance I recently performed on my engine.  I replaced all
three belts and replaced the spark plugs (with bosch standards) a few weeks
ago.  Could this have affected my timing and caused advanced or late
ignition?  I also put on new rear rotors and brake pads, and changed my
differential oil to Red Line 70W/90 diff fluid.  I can't see as how those
would affect this light, but then again I don't know how it is sensed.  If
anyone has any knowledge of this fault code I would be very grateful for
your help.  Thank you.

Sean A. O'Rear

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