So I dropped The D'Fer into West End Diesel Service for a look over the timing, injectors and FIP.

Injectors and FIP were given a clean bill of health, although the timing was a little advanced - plunger depth was 1.59mm.

I asked Greg to wind it back to specification (1.54) to see what difference it makes (if anything). The knock is still there at idle and according to Greg (the Manager at West End Castle Hill it is exactly like some, but not all 300tdis he has seen over the years, including his own D1.

Apart from a slightly larger puff of black smoke on start up, there is no discernible change in power output. The engine feels strong and revs smoothly and cleanly. With all the other tidy up work I've been doing The D'Fer is bliss.

It's Greg's advice that I should leave well enough alone. Yes, it's a little noisy at idle but not something that I should concern myself with.

Perhaps I should just turn on the radio or invest in a little more Dynamat.