C5 - weird sound

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salik1992
Posts: 2
Joined: 05 Jul 2024, 08:04

C5 - weird sound

Post by 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
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Re: C5 - weird sound

Post by PaulC5 »

Check all the exhaust clamps/brackets in case one of them has rusted through.
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Paul-R
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Re: C5 - weird sound

Post by Paul-R »

Does the speed of the clicking change with engine speed? If yes, is engine speed or half engine speed?
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salik1992
Posts: 2
Joined: 05 Jul 2024, 08:04

Re: C5 - weird sound

Post by salik1992 »

PaulC5 wrote: 05 Jul 2024, 12:06 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.
Paul-R wrote: 05 Jul 2024, 15:12 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.
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Paul-R
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Re: C5 - weird sound

Post by 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.

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As I get older I think a lot about the hereafter - I go into a room and then wonder what I'm here after.

Inside every old person is a young person wondering what the hell happened.

"Trying is the first step towards failure" ~ Homer J Simpson​