Go to dealer buy 6 or 8 (4.4i) sparks and sensor, open engine top cover, unscrew all 6 or 8 spark cables, replaced them with new sparks. Put everything back together => done. This cost me less than $75 and just an hour working on a weekend summer day.

I have replaced my BMW 2003 328I for my wife last summer when it was around 61K miles and my local MD Motorwerk guy in NJ told me it's time to do your inspection II (60-75K). And yes you should not wait until 100K Miles to replace your sparks. At this around 100K miles it may burns and defects your entire oxygen sensor and sparks cables.