Condensation under oil cap

[Bdc101]

With all due respect, I don't think that's true. I've never once seen mayo before and have been wrenching for many years. I used to own several MR2s which are notorious for having long warm up times due to large coolant volume and common thermostat failures, and even when I had very short commutes and stuck-open thermostats I never saw mayo once in hundreds of thousands of miles. My 2009 Scion and skyactiv Mazda do not have this problem and have been subjected to over a year of the same commute as this BMW with no sign of mayo.

Also, this car only took one day to build up more mayo under the oil cap, and as I mentioned above, reached operational temperature on each drive that day. So it's not a problem with failing to reach temp.