4 Answers

It means the oil is getting too hot and burning. This happens because the car has been driven without the proper amount of oil in it causing moving parts to get to hot due to friction from lack of lubrication.  Check your engine for leaks. If there are no leaks, then keep up with checking your oil level better.  

Since your oil is now burnt and back, I recommend an oil change as burnt oil no longer has a lube in it.  Get leaks taken care of as soon as possible and check your oil level within a few days of having the oil change done. It should still read at the full mark. 

Time for an oil change!

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This works for me. I use 15-40 oil in every car I ever owned regardless of owners manual. My last Corvette from day one had this put in it. At 360K miles I removed a valve cover and the engine looked as if it were built the day before. If the car has high mileage, drop the oil, replace with three quarts new oil and two quarts Kerosene. Drive it for two days and drain and replace with new oil. Engine oil pressure will improve, car will run cooler, and quieter.