so ive noticed over the past week the my car is now making a ticking sound. it sounds like its commin from front of the engine(front of the engine, not the bay). it sounds the same as a nocking valve but its subtle and it runs fine. however, the car when drifting at around 60mph does make a slight but audiable differance in the normal smooth exhaust note, but again, runs fine. i know it has to be commin from the engine because the ticking fallows the revs. i though it was the power steering because there is a leak and i have to fill it every now and then but i filled it up and the sound didnt go away. anyone have any thoughts? i cant imagine it being a head problem but ive herd of valves sometimes sticking, is this possible