My a4 2.5 tdi 180 seems to have developed a tapping noise coming from the top end It only does this when cold on startup its noisy at first untill the oil reaches the hydraulic lifters for 2-3 seconds then there is still this faint tap which stays untill the engine is fully warm. The car purs lovely when warm with no noise, there is plenty of power with no smoke and i cannot fault the drive. I have tried all the cheap remedies like oil change engine flush etc to no avail
The noise is coming from the right hand bank. I religiously change the oil every 6k with proper vag spec fully synthetic oil and i have looked down the filler tube with a torch and the cams look spotless on the two lobes i can see.
Does this sound like i am going to need a full top end rebuild as i hear horror stories about the chocolate cams fitted in these engines. It's a 2001 AKE with 134k so right in the ball park for this problem
Have any of you guys had simular issues?? or could it be something more simple??