2.0 TDI BRT engine produces a subtle ringing noise

Hello diesel mechanics,

The 2.0 TDI BRT engine in my Sharan (year 2007) --> purchased with 90,000 km on the odometer --> made a faint ringing noise in the background from the very beginning when it was running.

- It only 'rings' when the engine is running ---> it doesn't ring when going downhill in gear --> it rings equally when idling and when driving.
- I can't hear it anymore at higher speeds.
- Sounds the same whether it's cold or warm.
- Even after 30,000 km, it still rings (90,000 km at purchase --> now 120,000 km).
- The timing belt was replaced upon purchase.
- I can't definitively say whether it's on the timing belt side or the other side. It's audible on both sides, but not directly in the middle of the engine.

I didn't complain about it back then because I didn't notice it (it's possible that it has gradually become louder?). But the longer you know the car, the more you start to pay attention to the details.

I once recorded the sound as an MP3 file. With the hood open, I moved the MP3 recorder stick twice from left to right across the engine. That's why the sound, which is occasionally more noticeable as a ringing, is sometimes clearer in the background. However, it's always there (except when going downhill), and it's also audible inside the vehicle or when driving past a wall with the window open.

I've also heard it before from one or two other diesel vehicles that drove past me.

I hope you can give me some advice on what it might be and where I should look. Otherwise, there are no other unusual noises coming from my engine. The turbo is also running 'normally' (I occasionally check the data with VCDS). Fuel injection quantity deviations are between +0.2 and -0.2 for all cylinders (according to VCDS, the tolerance is up to +-2,).

Best regards,

Hello,

I couldn't detect anything unusual during the listening test.

Possible causes of doorbell sounds:
- Loose parts, such as a random screw or a pressure piece on the clutch (the bell will stop ringing when the clutch is pressed).
- Resonance from various aluminum castings, for example, the mounting of the AGR cooler without the engine cover in place. If you tap your finger: *piiing*
- Piston tilt
- Combustion (gasoline engines), not applicable in this case.

At least, according to my ears, I wouldn't worry too much right now.

Best regards, Rainer.

Thank you for the initial tips.

The noise is still there when the clutch is depressed.
I probably need to check all the parts again to make sure nothing is loose. I tend to remember the sound of a piston pump more as a thumping noise, rather than a ringing sound.

This ringing sound is more noticeable towards the end of the recording in the MP3 file.

I'm a bit 'concerned' about it, as it's my first diesel car, and I'm not familiar with all the sounds in the 'range of noises' it can make.

Okay, I'm not hearing anything particularly unusual right now.

Perhaps a very faint ticking sound, if at all.

newt0n wrote:

- It only "rings" when the engine is running ---> it doesn't ring when going downhill in gear --> it rings equally when idling and when driving.

Does the engine make a ringing sound when it's pushing?

Then it's the solenoid valves of the pressure-dependent elements.
Sometimes you can hear them snoring. Because the injection is deactivated in "glide" mode, the noise disappears. If you press the accelerator gently, you can hear that rattling sound again.
Only when this noise is no longer present does it become critical for a PD motor (unless it is a PPD).

The engine sounds completely normal for a PD engine.

If the motor pushes, does it not make a sound?

Yes, that's exactly it; when the motor pushes, it disappears.

I don't hear this noise with every PD-diesel engine I encounter, but I do hear it with mine, and in rare cases with others (in one instance, it was a Passat).

I will check the metal parts for proper mounting at the next opportunity, but otherwise, I won't do anything else for now. It's been there for at least 30,000 km. It seems to me that it has increased slightly, but maybe I'm just becoming more sensitive.

Despite everything, I still love my Sharan, no matter what 'noises' it makes. It's simply a fantastic car for a family with several children. And so far, I've been able to handle the suspension repairs myself. I have absolutely no experience with engines, and I'm trying to learn here in this forum.

It's running smoothly, this Magnet-PD .

That sounds normal to me too.

I'm going to record something tonight (again, it's so late) about our 1.9 PD Golf 5 (BLS).
I can perfectly replicate the effects of injecting [something] here, on this mountain, and also the effects of not injecting it.
It's also loud enough to hear a difference.
My PPD Passat is noticeably more subtle.

You can also provoke it yourself:
While stationary, give it a burst of gas.
The engine is revving strongly.
If you completely take your foot off the gas pedal, it will rev down without fuel injection.
and then it will be "intercepted" again.

Approximately like this: (r == idle, R == high RPM, .. == nothing)
rrrrrrrrrRRRRRRRRRRRR.........rrrrr

m;

Wow, the car sounds so different on the iPhone.

- Recordings from inside are unusable because you can't hear anything.
- There's too much wind blowing outside while driving.

Therefore, here are the gas bursts that I mentioned:

Quote:

rrrrrrrrrRRRRRRRRRRRR.........rrrrr

Today, I recorded the 'ringing' sound again and noticed that it is much more noticeable coming from the two wheel wells.

The engine was warmed up. I then briefly turned it on and recorded the first half of the footage next to the wheel arch on the driver's side, and the second half next to the wheel arch on the passenger's side, while the engine was idling.

This time, I could clearly hear the ringing.

Sure, here's the translation:

'Again:'
- It only activates when the engine is also injecting fuel, so it doesn't happen when going downhill in gear.
- It's also present at higher speeds, but we're completely overwhelmed by it.

I don't usually hear that noise in other diesel engines, which is why I'm asking.



This morning, when the engine was cold, it barely made any noise at all; it only started making sound after a few minutes, when the engine warmed up.

Overall, it has been present for at least 30,000 km, but I feel that it has become more noticeable recently.

Please listen to this.
Thank you.

I still think it sounds like a normal, old PD-TDI engine.

"It's not exactly new anymore."

m;