| I have a 2000 323i and just recently have had a misfire cylinder 2 trouble code. I have the big bently service manual to guide me through my repairs. I descided to change all the plugs and plug boots while I was replacing a coil. 2 things to note:
1) CAUTION The bently service manual has a warning note to only relace an individual coil with the same manufacturer's coil and part number. Why I don't know. It doesn't say. It continues that if you are going to switch manufactures then all 6 coils should be replaced at the same time. My car has Bosch coils. My parts supplier sent me a Bremi coil. Now the car is out of service until I can get it straightened out.
2) History. I have been chasing an intermittent hesitation at low power settings for a few months now. When easing on the gas at stop lights or after pulling out of the garage I could regullarly feel small hesitations. It felt like the automatic transmision was shifting through the gears. However, if I really stood on it off the starting line no hesitation was felt. No hesitation once up to speed at any time. Recently a trouble code was logged on the computer and the check engine light came on. The misfire cylinder 2. The engine was missing all the time and vibrating badly. Removing the plugs today confirmed a black sooty plug on #2 and greyish brown on the remaing plugs. Bmw dealer I spoke with knew right off hand what was going on before I even told hime the trouble code message and stated it was a common problem he had been seeing lately.
I might just go ahead a replace all the coils with the other manufactuer's part if they cronically go bad. At 60 bucks each it wont be cheap, but if the original parts are unreliable then it would make sense. I hope this fixes all the hesitation problems. | 
