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.
Is it consistant with a certain brand of fuel, certain type of weather, amount of time your car was sitting before that particular time you drove it, a certain type of driving (i.e. hard acceleration etc)....?