Hello, I have a 2.0 TDI 64 plate common rail.
Engine often makes a rattle/knocking noise in startup, it has stalled once and sometimes doesn’t clear until I turn off the ignition and try again and then the sound isn’t there and the engine starts smoothly.
I have changed the timing belt and tensioner and water pump since, and the sound is still there so that can’t be the issue. The timing is fine also.
It just makes no sense to me, it it was mechanical it would be there very time constantly, but it is intermittent. What would you guess it could be, have you had the same problem? Link below.
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