Citroen C5 X7 Strange noise at the engine

[vladd.alex]

Hello dear colleagues.

I have recorded a short video to show an issue that I am trying to face off now on my X7 2.0 HDi 163 HP FAP. On the left side, I hear a strange noise, like a bee. It is close to the timing belt. Do you have any idea what can be the source of it? Sometimes the sound disappears.



And an additional thing, every time after I stop the engine, I hear a short sound in front of the car, like a creak. Can this be a valve from the suspension or?

Thank you very much,
Vlad.

[ekjdm14]

The buzzing sounds to me like an electrovalve/solenoid/servo of some sort, possibly EGR actuator as I think they make a buzzing sound (certainly I remember posts on here where people had asked about similar noises & it was this anyway).

[EDC5]

The buzzing sounds to me like an electrovalve/solenoid/servo of some sort, possibly EGR actuator as I think they make a buzzing sound (certainly I remember posts on here where people had asked about similar noises & it was this anyway).

I would second this as it does sound like a buzzing solenoid. However it would have to be pretty loud to hear over the engine.

Perhaps you can try the solenoids individually through lexia to see if you can reproduce the noise without the sound of the engine interfering.

[vladd.alex]

Thank you for the suggestions. A few things I can eliminate from the begining, such as the accesories belt, the pre-tensioner and the alternator. These I have changed/tested. I know a few other C5 owners with the same noise and it is strange. I just want to be sure that if I go on a long trip with the car, abroad, I will not have some trouble.

I think it is a good idea to check the valves via Diagbox, one by one. Beside this, as an additional info, I have removed two days ago 0,5 l of LDS, is was over the high level, with the system depressurised. And the LDS looks not so good, more black than red. How fast shall I change it?

Best regards,
Vlad.

[vladd.alex]

I have found today the source of that buzzzzzz noise. It is a pipe going in something (I don’t know in what), if I block that pipe with the fingers, the sound it’s gone. Also, after every engine stop, I hear that buzzzzz very hard for 2 seconds. Is there a vacuum attic actuator or something? Shall I change it or try to repair?

[vladd.alex]

I have made today two photos. Where I've added the green arrow, that's the hose.

[leocitroen]

Hi,

My car, the same engine as yours, had that problem. Also in my case if I block that pipe with the fingers, the sound it’s gone. The problem was with the solenoid. I replaced it and the sound stopped.




It's a rounded valve: 1618QQ ELECTRO VALVE

I bought a used car valve (2014.) and paid 25 €, and I replaced it alone.
P.S. you will need a little mirror and magnet for the 2 nuts you remove.
I hope you will succeed in solving the problem.

And yes, I have posted this post earlier.
viewtopic.php?f=3&t=55066

Now I UPDATED it!

[vladd.alex]

Thank you for replying Leo. Would it be possible please to post also a link with the real part? Thank you! And an additional thing, are there two identical solenoids?

[vladd.alex]

Leo, I have found a picture with the rear side of the engine. Which of the two identical solenoids have you changed? The left or the right one, according to this photo?

This is the part, about 20 Euro.

https://www.autokarma.ro/convertor-pres ... pa_order=8

[leocitroen]

Yes, that's the valve. In my case it was right from the picture .. it was rounded up in my post.

[vladd.alex]

Ok, so that valve which is going to the turbo. Could this affect also the functionality or it is just a matter of noise?

[leocitroen]

In my case there was no difference in the functionality of the car "before this sound", while the sound was there even after I replaced the valve.
I do not know the correct function of this valve .. (maybe someone who knows could explain a little).

[vladd.alex]

I think I understood you wrong. The sound is still there even if you have replaced the valve? Or now you have not anymore the sound?

Now regarding the functionality, the right valve (from the engine photo) it's modifying the turbo variable geometry, which will ensure that you have a higher turbo speed even on low engine speed values.

The left valve I assume it's going to the EGR.

[leocitroen]

NO, there is no sound anymore. However, while that sound existed and after changing the valve I did not feel any problem with the car.

[vladd.alex]

Dear Leo, thank you so much! I have replaced the valve today and the sound has gone! More than this, I have the feeling that the turbo is starting earlier, because the acceleration is better now.

Just one observation, the first hose was very easy to be mounted over the tube from the valve. I hope it will not fall down.