Ticking! Cause:

Hi,
As I can see here, this ticking sound on TDI engines is not uncommon, because I also observed and 'fixed' it on my 1Z.

As I mentioned in some of my previous posts, I installed a capacitor for the earlier fuel injection timing. After a few kilometers, I suddenly started experiencing this ticking sound, and I didn't think much of it at first. However, I realized that the load on the engine was too high (early fuel injection timing = higher oil temperature), so I replaced the 100nf capacitor with a 30nf one. The oil temperature then returned to normal (I think), but the ticking sound was still there.

Two days ago, I removed the capacitor, and I immediately noticed that the ticking sound was much quieter, and secondly, it no longer existed constantly, but only occurred occasionally.

Since my 1Z engine is also chipped, I think I might have set the fuel injection timing too early.

Conclusion: Based on my findings, I believe this ticking sound could also be caused by premature fuel injection.