Whining noise on 1.4 TDI engine

After driving my car for 70,000 km (which has actually had quite a few problems), and having taken it to the workshop regularly for several weeks due to a rattling/whirring noise (especially noticeable at idle), I'm receiving new bad news every day! I believe the noise has been present from the beginning, although not as loud. However, a few weeks ago, when I took the car to the workshop because of the noise, they said it was the water pump and/or the timing belt. After replacing all of that, everything was the same; the rattling/whirring continued! Then, they thought it was a vibration damper on the crankshaft. They replaced that last week, and the result is: that wasn't it either! Yesterday, I was told it might be the 'collector' (what is the correct German word for that, actually? ). Today, while working on the turbo, they also noticed that it seems to be leaking oil!!! Now I'm also getting a new turbo, but not before Monday, because the part needs to be ordered!!! I don't know, but I'm really fed up! I just want to drive my car without any squealing or whistling noises, but apparently that's not possible. I'm disappointed with my car, and as a student, you can't just buy a new one. But what could be the reason why the turbo is losing oil? Is it possible that the turbo is already damaged if there's too much oil in it (or has been too much oil in it)? I drive the car very gently, always warm it up carefully, usually let the engine run for a few revolutions before turning it off, and always check the oil, etc.! Yes, what else do I need to do for everything to last? 70,000 km, that's not the world!

So, if you drive the TDI described below, you won't be surprised.

I've driven several 3-cylinder engines, and only the one with 90 horsepower impressed me with its performance.

You can just throw everything Laufkultur stands for in the trash.
The idle is just very rough; maybe you have to accept it.

Or invest in something else!
People who buy a car like that are really just looking to save money on fuel, and somewhere along the line, there are always compromises.

If I were to buy a PD engine, I would only consider one with 115 or 130 horsepower.
"However, even the one with 115 horsepower feels a bit too restricted at the top end!"

Hi,

Do you have to pay for the new turbo yourself, or is it covered under warranty/goodwill?

If that's the case, I would definitely have someone else take a look at it, because a little bit of oil leakage from the bearing housings is normal.

Was your noise really annoying, or just a little disruptive? If it was just a little disruptive, then you probably have to accept it as "normal" or do something about it yourself. My Ibi also has some issues, but they are mainly caused by the instrument carrier, and I think they can probably be fixed with a little tinkering (if I ever find the time).

Best regards,

Jan.

Regarding the first response: When driving 150km daily, I'm not necessarily looking for high performance or a refined driving experience, but rather reliability and fuel efficiency! The 1.4 TDI is fuel-efficient and powerful enough!

Regarding the noise: it was and still is annoying. When the engine is really warm after 130km, you can clearly hear the scraping/rattling/whirring (which is also uneven and irregular) inside the car, even when idling. Since other Polos with this engine don't do that (my first one didn't either), I assume that this is not normal.
Furthermore, my car is only 1 year and 9 months old, so the turbo and everything else is still under warranty!

Hi,

If that's the case, I would insist on a thorough rework, especially if you know that other cars with the same machine don't have the same issue (because that undermines the argument that "it has to be this way").

I still don't believe that replacing the turbo will solve the problem...

Are you sure that the noise is coming from the engine compartment and not from the instrument panel?

Best regards,

Jan.

I don't think a new turbocharger will solve the problem, but they saw that mine is somehow leaking oil, so now they're replacing it.
The noise is clearly coming from the right corner of the engine compartment (as viewed from the driver's seat), and also from the right wheel well.
'You could even tell me that the noise is okay, but I just don't want something to break after the end of February, when the warranty expires!'
'Turbocharger and noise, in my opinion, are 2 different things. There's a noise that's constantly present and isn't normal, and on the other hand, the turbocharger has already worn out after 70,000 km of careful driving. What could be the cause of the oil loss? Does anyone know? Is it possible that there was too much oil in the engine, or is too much oil 'not' harmful to the turbo?' Besides, I doubt I added too much oil in between.

Okay, there's a promotion where the fuel feed line in the engine is being replaced (modified).
Since the pipe can pick up vibrations and transmit them to the body.

The impulses originate from the pump nozzle elements and then propagate.

I don't know how well that description applies to you.

I had performed the procedure on an Audi A2. The customer did not raise any further complaints afterward. The new design features two round side chambers where these vibrations are intended to be absorbed.

Having driven approximately 190,000 km with the AMF, I, as a technically interested amateur, have come to know a few of its quirks.
Despite this, it is, by far, the most elastic and economical engine in this performance class. There simply isn't a comparable competitor product. The only engine that comes close is the four-cylinder from Toyota, but it cannot compete with the AMF or the 90-horsepower version in any of the mentioned areas.
Furthermore, the engine is quite tolerant when it comes to chipping. This means that even without a Variable Turbine Geometry (VTG) system, the turbo lag can be practically eliminated by accepting a little bit of smoke under full load in that specific RPM range. PÖL compatibility is also available, unlike common-rail systems.
The engine noise doesn't really matter to me, so I'm not an expert on that. If I want sound, I'll drive an American V8 muscle car... or, alternatively, a Japanese high-performance car. BMW's inline-six engines offer a smooth and quiet idle.
Tractors are tractors, after all (especially those with PD engines). That's why PM motors also offer significant advantages in terms of power and energy consumption.

Subject:
"The chirping" is coming from the fuel filter. It seems that newer models have probably resolved this issue. However, a new diesel filter should provide some relief even for older models. A little bit of dirt in the filter, especially in cold weather, could quickly cause the noise to return. Alternatively, you could also turn up the radio or install rumble strips in the dashboard (which will at least be more annoying in turns).
To be sure that it's the problem I described (but given the localization "front right," I'm quite certain):
Just fill up with biodiesel or rapeseed oil. If the noise gets louder, then it's the problem described.
Be careful: if biodiesel has never been used before, the diesel filter may become clogged and need to be replaced.

I hope I was able to help.

Olaf.

P.S.
I don't know what "gentle driving" is. But if you let the engine run for a few minutes after a cold start and then occasionally give it some gas, it won't hurt. Otherwise, the car will never warm up in the winter and will constantly run with completely cold oil. I've noticed more strange noises coming from engines that aren't driven properly. You can also exploit the power of an engine without ruining the clutch and transmission. The performance of my system is also becoming increasingly worse if I don't put it under load for weeks.
Regarding oil and turbochargers:
It's normal for a small amount of oil to seep out onto the exposed side through the shaft. Therefore, the AGR (Abgasrückführung) valve is likely defective. Russ and oil make a great sludge.
Eventually, so much oil will accumulate on the intake side that it can't all pass through the engine, which can suffocate the mass airflow sensor and trigger an error. The engine will then go into limp mode. At that point, it's necessary to verschandeln everything and have the turbocharger repaired (new bearings, balanced). If you continue driving for a long time, you risk the turbocharger shaft developing so much play that the impeller blades hit the housing, scattering metal debris everywhere. Suddenly, the oil consumption spikes dramatically, creating a risk of unknowingly running the engine dry (all the engine oil spontaneously migrates into the intake manifold).
So, I would wait until just before the warranty expires to report the issue and have the charger replaced. The earlier you do it, the more kilometers you're essentially giving away, kilometers you could have still driven with the old charger.
When that time comes likely depends largely on the number of cold starts. It's also not ideal to immediately turn off the engine when the turbocharger is very hot (a typical situation when you quickly stop for gas after a fast highway drive). This can cause oil sludge to form in the oil supply line to the turbocharger. If the turbocharger then doesn't receive enough oil, the bearings will wear out more quickly. Increasing the boost pressure (through a chip) naturally amplifies this effect. A boost pressure control system that overshoots (causing pulsating acceleration) also has a negative effect. The loader experiences extremely high pressures in the short term, which puts it under a lot of stress.
Under reasonably normal circumstances, even a vehicle with a chip modification should be able to last at least 100,000 km. Since there's no VTG (Variable Transmission Gear), there won't be any issues in that area with the AMF (presumably referring to a specific model or system).
I can't say for sure what is most likely to cause the loader to fail, as loaders with this type of engine don't usually break down (unless the wrong oil is used).

P.S.2
The explanation given by "Steffarn" sounds quite plausible. It would also explain why the sound changes depending on the type of fuel (due to different density/viscosity).

Could it really be the diesel filter?
Okay, so, regarding the noise: it's a regularly irregular whirring/rattling sound, like 'schschschsch...schschschsch...schschsch,' which is particularly noticeable from the outside when the engine is idling. However, it is still audible even when I slightly increase the idle speed.
Regarding the turbocharger: the mechanic said that it was likely leaking a small amount of oil around the shaft area.

I think I'll tell them about the idea with the diesel filter and fuel lines the day after tomorrow, and then we'll see what happens.

Regarding the turbocharger:
My statements specifically referred to the oil being pushed by the wave.

Regarding the sound:
What I mean is a very high-pitched (!!! which is why many older people probably won't hear it) whistling sound, coming from the front right side of the car, and it's especially noticeable when the engine is idling. I don't know if it can be heard from the outside (I've never really been interested in that). However, it seems very likely that it's the same sound that Steffarn mentioned with the A2. The sound I'm observing is definitely related to the fuel lines. Just try the test and fill up with biodiesel. If it gets stronger, we're talking about the same sound.

Regards,

Olaf.

I would like to use biodiesel, but as far as I know, there is no biodiesel available for purchase in Luxembourg.
My noise level is not very high, however...

You can also use PÖL (a type of fuel additive) from Aldi or Lidl for testing. However, please don't use more than 15% in cold weather (below 5 degrees Celsius), especially if you frequently start the engine when it's cold, as this can put a significant strain on the timing belt and other engine components. Otherwise, if the tank is empty, just pour some in and test it, and before a long period of inactivity, simply refill it with diesel overnight.

But it seems like it's actually a different sound... "chirping" describes it quite well.

Regards,

Olaf.

What should I consider when getting a new turbocharger? Do I need to 'break it in,' or does it not require any special attention?

I finally have my car back, with a new turbocharger, but the noise is still there! They are now contacting the factory to see if they can find a solution.

I just went there again, and they told me that my old turbo wasn't showing any play in the shaft, unlike the new one! So, in my opinion, the old one was probably still perfectly fine. Also, my car used 450ml of oil for 20,000 km.
However, we haven't made any progress with the noise yet!
But my car drives great, just like always!
I read somewhere else that it could also be the warehouses of Lima. What do you think?

As I mentioned before... a little bit of oil seeping through is normal. If the engine isn't being used much, it unfortunately accumulates on the side exposed to the open air. The only solution is to give it FULL THROTTLE!!!!!!!!!!!!!
450 ml is quite a lot... but not really too much... actually, it's perfectly within the acceptable range.

To the breast lift:
Then the noise probably isn't coming from the front right side...

Regards,

Olaf.