2010 CTS4 sedan has been having the same code P0017 come up which is for crankshaft and camshaft positioning sensors not correlating. I've only bought the car 4 months ago. When I bought the car it had the code but the dealership fixed it. They changed the sensors for both crankshaft and camshaft but didn't fix it so they changed the timing chain which they thought was stretched. The code went away for a couple months but now its back. The same dealership changed the time chain again but the codes didn't really go away. It was off when I left the house but when I was running errand it came back on so I ran the codes and it's still P0017. But on the way home it was off again. Any help is appreciated cause I'm losing hope with this damn thing.