[TitanicSnake]

Hi,

Does anyone have any experience with this type of noise on a Bx8 petrol engine?



Video comes from youtube and a B48 engine but I have the same exact type of noise on my B38 F40.
The noise appears some seconds after the cold start phase has ended and goes away after ~10 minutes.
It does seem to be louder under the car than near the engine bay.
Car otherwise runs normally with no codes on ISTA and updated to
the latestet RSU i-level 11/2022.
I also tried disconnecting the purge vent valve but the noise did not dissapear.

Thank you in advance

[vanos]

Press the brake pedal several times in succession. Any change ?

[TitanicSnake]

Press the brake pedal several times in succession. Any change ?

Hi vanos,


Thank you for your reply.
I've just tried your suggestion this morning, but it made no difference whatsoever

[larshutten]

Is it same sound as attached file?

IF YES:
- let engine run (80 degrees celcius if sound is still there but softer pres brake pedal several times, if sound goes away go to next steps)
- locate the sound if near engine oil sump go to next steps.
- check engine oil level, if on maximum or to high replace engine oil with filter.
- if oil level is not at maximum or lower replace oil vacuum pump(oil pump)

there is puma case about it

[TitanicSnake]

Is it same sound as attached file?

IF YES:
- let engine run (80 degrees celcius if sound is still there but softer pres brake pedal several times, if sound goes away go to next steps)
- locate the sound if near engine oil sump go to next steps.
- check engine oil level, if on maximum or to high replace engine oil with filter.
- if oil level is not at maximum or lower replace oil vacuum pump(oil pump)

there is puma case about it

Nope that is not the noise.
What I'm hearing is an irregular ticking/clacking that goes away as soon as the engine starts getting hotter.
It's frequency does seem to increase with engine rpm (see attached audio)

[user0086]

-What i-level do you have? The wastegate control loop is unstable on pre-2016 software.-

Nevermind, didnt read the first post completely...