I recently purchased my wife a 2000 STS very nice powerful car. We have had it since Christmas and have had no issues. 3 Weeks ago the low oil light came on. Whebn I checked it IT WAS EMPTY. I had to put 5 quarts in it to get the light to go off. Went out to check it last weekend and found it was a quart low again and I guess I did not notice it before but the insulation blanket under the hood was soaked with oil. I could not find any oil on the motor itself as well as no drips underneath. Took the STS into the repair shop and they cannot find ANYTHING WRONG!!!! They went all over it and could not even find any oil drop anywhere. WHERE IS IT COMING FROM???/ Has anyone else ever expeirienced this???/?? Nothing underneath checked oil cap, dip stick and pcv valve all good. THere is literally NO OIL ON ANYHING!!!! Please help if anyone has any expierience with this. My mother in law had the same thing on her Deville a few years ago and they could not find anything on hers either. (Different repair shop).