I was washing my spoiler on all surfaces of my C4S when it was in the up position and discovered when I was cleaning the black rubber/plastic accordion(?) part of the spoiler that it was loose from the engine cover......low and behold the little round black lock washers used to affix the accordion device to the engine cover were missing. There are six of them and three were missing.........just a heads up to others......I went to Home Creepo and found some # 10 silver (with (little teeth type) lock washers in the hardware section with the nuts and bolts......worked better than the Porsche lock washers....it does appear though that they overspray the ends of the bolts with the original set-up after the lock washer is put on with a black acrylic material as extra insurance to hold the washer in place.......didn't work with mine.........next time you are washing your spoiler surfaces...check it out.......I will use some silicone on the ends of the bolts to simulate the black acrylic...........