C5 - weird sound

[salik1992]

Hello everyone,
Recently I have noticed a weird rhythmic metallic sound coming from the rear left corner.



- Car: Citroen C5 Tourer 2017 with 2.0BlueHDI
- It is inaudible from the cabin even with driver's door open
- When standing at the rear, it sounds "distant", only when getting close to the rear-left wheel / exhaust, it is properly audible
- I've never heard it after startup
- It stops with the engine
- I've tried citrobatics and all seems to work fine, rocking the suspension is equal in all corners, switching to sport makes all corners equally harder
- I've checked LDS level on the lowest setting and there was no fluid visible above the grill, but from what I understood that wouldn't be if it was filled properly
- The car was rebuilt by czech citroen service about a year ago after front-left impact in late 2020 but I bought it only last autumn (2023) so I do not know the full history

[PaulC5]

Check all the exhaust clamps/brackets in case one of them has rusted through.

[Paul-R]

Does the speed of the clicking change with engine speed? If yes, is engine speed or half engine speed?

[salik1992]

Check all the exhaust clamps/brackets in case one of them has rusted through.

Thanks, for the tip, they all seem fine and the sound is too regular.

Does the speed of the clicking change with engine speed? If yes, is engine speed or half engine speed?

Yes, I had an opportunity to test it. It definitely is connected to engine rpms. If I had to guess I'd say it's 1:1 connection (double rpms result in double frequency of the clicking) but I'm not 100% sure with this as the increased engine volume nearly drowns the clicking completely at that point.

[Paul-R]

I don't have any idea at the moment but maybe using an engine stethoscope will help to narrow down where the noise is coming from.

https://www.ebay.co.uk/sch/i.html?_from ... =0&_sop=15