Engine sounds like a diesel car…

[snowy792]

Hi all,

I have a 2008 Manual 3.0si with 89k miles
For the past month or so my engine has been making some unusual sounds..

There seems to be two components to the sound, a higher pitch fast ticking and a lower pitch slow ‘chugging’ sound like a steam engine

The ticking sound may be the VANOS system as seems to be a common nuisance on this engine. I am more concerned with the ‘chugging’ sound audible in the first section of the attached video

Both sounds are independent of engine RPM and temperate (appear when engine is hot or cold), and most audible at idle
The car also has a wandering idle when starting

Additionally there is a sort of hissing sound from the engine bay, vacuum leak?

I have another car to drive while I’m diagnosing the Z4

I plan to change the oil and investigate the DISA valve (I am aware these no longer fail catastrophically but can allegedly still make a rattling noise)

Does anyone have any pointers or suggestions of what to investigate?

I’m not against taking it to a specialist but I usually do all my own mechanical work.

Best regards,
Mark

 

[lucasxdiniz]

I can hear your DMF being noisy and injectors ticking. Both common sounds of the N52. DMF being particularly noisy in all 3.0si I've ever been in, especially at idle and when turning the engine off.