This bulletin applies to 2014 Mini Cooper vehicles equipped with a 1.6L engine. An oil leak can develop at a sealing plug located in the cylinder head, just below the vacuum pump.
Pop Goes the Rear Mainseal
Some owners of 2011 Buick Regal vehicles equipped with a 2.4L engine may complain of an engine oil leak that appeared in extremely cold ambient temperatures (generally 0 degrees Fahrenheit or colder). They may also comment that they heard a single “pop” noise immediately before the oil leak started.