My td42 has about 3 times that I'm aware when idling gets this real loud knocking noise and runs rough but only for a couple of seconds. Best way to describe it is sounds likea big end bearing gone. I'm guessing its injector knock as I had the injectors done up just before the first time it happened. This was about July last year.
Could injector knock be this intermittent? It goes fine except for them three times. And I guess what can I do to stop this happening.
may be loose pre comp chamber/ers. when i got the head off mine 2 of these fell out. it had a slite knock befor this which sounded sort of like blocked injector/ advanced timing sort of thing hard to explain on a computer. duno just my 2 bucks