2007 335xi. 100,000 miles. Always serviced at dealer as in manual. No previous issues.
Take in when a slight hesitation felt at low rpm when acceraltion asked for is anything more than modest. My OBD reads misfire in cyclinder three, O2 sensor fault. Plugs replaced at 90,000 so I suspected ignition coil. Diagnosos was oil in coil, caused by oil leak from gasket associated with oil filter, and O2 sensor triggered by cracked value cover. Was told "gaskets go at 100k as materials required to be biodegradable, other than Bosch coil have issues, and no ide on cracked value cover. Repairs will be $5,000. I've not seen anyhing similar on the site. I'm shocked. I asked for the bad parts back.