I'm getting code p1336 on my 02 Nissan Frontier 3.3. My truck was fine with no codes and I decided to do a cooling system flush and code p1336 popped on. I don't know if the flush caused it, but the truck runs fine with no symptoms. When I search the code it says it's the crankshaft position sensor. If my crankshaft position sensor was bad would I have any symptoms, what else could cause this code?