I have this EXACT issue on my 2008 X3... weird trans hesitation/pulse but only under heavy acceleration. Can you give me any more detail on the O2 sensor replacement?? Like cost and part number(s)??
Originally Posted by Etubom
Hesitation occured when under hard acceleration between 2800-3000 rpm. Would not throw a code for a long time, but finally did so 7 months ago. The problem was with one of the pre-catalytic converter O2 sensors. It was replaced, the problem disappeared and the X3 has been smooth as silk ever since.
('07 E92 328xi / '08 E83 X3)