Valve tap

That's pretty common, and is usually due to what's called "piston slap" as the horizontally-set architecture results in the loose pistons slapping their cylinders when cold. Once warm and isothermal the noise subsides as the piston paths become perfectly horizontal. In winter this can take a full 20min of driving (not just idling). Are the cylinders being scored each cold start, reducing longterm durability? I dunno...2000-2012 SOHC 2.5i are usually tossed for other reasons. Now, there IS a chance that valve lash was not set up correctly when the heads were "done". But given the noise-quenching with warmup I'd doubt that's the problem. So try not to race the motor when cold for quick warmup, eh. Maybe use 5w30 winter instead of 10w40, but don't use 0w20 as you'll start consuming it! Best, Ern TSG/B