Based on some 'advice' from other sources that I should run my 2.7 diesel S Type at high rev's in order to spit out carbon build up (engine recently Terracleaned), I did just that recently and a loud knocking sound - not unlike a rogue tappet - ensued in time with the rev's of the engine.
Anybody any experience of similar happening?

 

I've heard of the odd injector needing replacing after Terraclean (I had to change 2 on my tdv6 after) but nothing else.

You may get a better response if you post this in the Diesel Variants section though 😊.

 

This must be a UK based product - never seen it before. I used a product called BG, and used in a similar manner for petrol.


It is possible that maybe some debris has become lodged inside the injector and this may be the source of your "knocking" noise. I have seen quite a few injectors needing replacement in the 2.7 and 3.0L Diesels...

 

It's running the engine on a very pure form of fuel, supplied through a machine, that is supposed to burn off carbon build-up. Sometimes Jaguar injectors have issues after this. I had two go to msximum offset the day after, but it wasn't making a knocking sound.