I purchased a Certified Pre-Owned 2007 4.8i in January of 2011. At the time, I went through and looked through all the service menus on I-drive, and noticed that my next oil change was due in Feb 2012 or at 14,000 miles, which seemed right. Since my purchase, I have driven 10k miles. A few weeks ago, I got an an oil warning light, so I scheduled an oil change (well in advance of BMW's recommended maintenance interval of 12 months or 15000 miles).

However when I checked the warning indication more carefully, I discovered that the warning light actually indicated the oil level was at the minimum level, and not that an oil change was due. I thought this was odd since I had only owned the car for nine months – how could it be so low with no signs of oil leaks?

So at my service appointment the next day, I told my service advisor about the warning light. Upon looking up the service records with the key fob, he noted that there had not been an oil change since Feb of 2010, meaning no oil change was done as part of the CPO process. This means I have driven my car without an oil change for nearly 20 months. As you can imagine, I am worried about any long term damage to the engine which may result in shortened engine life. At the very least, I would think another one to two oil changes at shortened intervals would be required to "flush" out the system due to having old, dirty engine oil circulating for an extended period of time. To their credit, they did not charge me for the oil change, which I appreciated.

What would you guys do?