Question about KKK turbocharger on the AEl

Hello.

I'm currently having a problem with the AEL in my Volvo - it's not producing any power.
Around 2000 rpm, you can briefly feel a sensation of air being compressed, but at 3000 rpm, it completely disappears, and there's no more power. The boost pressure doesn't exceed 0.4 bar (according to...). (Measurement) - however, 1 bar is required.
Based on this, I suspect there's a problem with the turbocharger itself or its related components. I swapped everything related to the turbocharger in the exchange process – from one vehicle to the other, vice versa – all the valves/sensors, and even the hoses – but it didn't change anything.
"The LMM (lambda sensor) has been replaced, and the pump adjustment has been made. Before that, I checked the timing cam (I was thinking that the timing belt might not have been installed correctly, considering all the random markings you see on these engines)."

The fact is, the engine was replaced at a Volvo dealership 150,000 km ago. Since then, the car has been sluggish, according to the former owner. I'm guessing it's around 80 horsepower.

My suspicion was that the wastegate was somehow stuck - the problem is, I'm not familiar with how it works. For example, on turbochargers in gasoline engines, you can directly see a valve that opens. On the turbocharger of the old TDI, you see a "hole" and a pipe. Can someone please explain to me how that works?

However, the valve itself seems to be working, as far as one can tell from the sound it makes (it opens when I suck on the hose).

I also removed the intake manifold yesterday - the EGR system is active - but to my surprise, it was quite clean.

One of my suspicions is that the turbo suffered damage during the engine failure back then, but this wasn't seen or detected. However, the impeller can be rotated normally (on the intake side).

It's also the case that you can't hear the turbo at all - you usually hear a slight sound when a new one is installed. Therefore, I also assume that the intercooler circuit is not broken – the hoses are fine – but if, for example, the radiator were to burst, you would see (oil) and also hear it, right?

"Someone might have a tip, especially regarding the function of the wastegate. I already have a replacement turbocharger on my workbench, and I'll be installing it today. Hopefully, that will give me a better understanding of the issue and allow me to resolve it."

Thank you.
Sure, here's the translation:

"Hello."

Okay, I'm ready. Please provide the German text you want me to translate.

dieselschrauber wrote:

/viewtopic.php?t=3101

THANK YOU!

Hey.

"I replaced the turbo today. Now I understand how it works. Unfortunately, the replacement didn't make any difference at all." Okay, I've tried everything now - it seems like the only possibilities left are the ESP (Electronic Stability Program) or the injectors. When I use a chip tuning system, there's only a slight improvement, I can hear the turbo, but then it cuts out at around 3000 rpm.
There's nothing more that can be done.
However, it then becomes very quiet, which is why I suspected from the beginning that the pump was malfunctioning. The setting is correct, however.
Could it be that something is wrong with the injection molding machine, or is there a problem with the pump?
I doubt that the pump or the nozzles are the problem, but I've already replaced almost everything else.
Between the mass airflow sensor and the turbocharger, there's a sensor – the part number indicates it's a PTC sensor – that wasn't connected. I found the connector, and it was completely corroded, meaning it had been "forgotten" to be plugged in for a long time. At first, I thought I had found the error, but it didn't change anything .

Does anyone have any more advice for me?

BTW, could it be that something is wrong with the engine? Should I consider having a compression test done, for example? "But somehow, none of it seems to fit together, as if the turbo just isn't kicking in - or what do you think?"

"Thank you."

best regards, uwe

Quote:

Should I, for example, consider having a compression test done?

No - why would I? As long as it starts, it also has compression.

Obtaining measurements of parameters such as boost pressure, EGR, and air mass would be beneficial.
What does the error memory contain?

Are the airways (intake and exhaust tracts) clear? Camshaft OK?

Hello.

"Thank you."

The system requests a boost pressure of 1 bar, but it only delivers 0.4 bar.

The intake manifold and exhaust manifold are clear. The mass airflow sensor (MAF) has been replaced (I have several identical vehicles, and I've already swapped almost everything between them for testing).

The exhaust system itself remains, but one might wonder: is there a mouse sleeping in the exhaust, or is the catalytic converter clogged?

I also have some nozzles lying around; I'll replace them tomorrow. Just like the wiring harness on the engine - it seems there's something wrong with the wiring.

Attached is a test measurement.

"Thank you."

Sure, here's the translation:

"Hello."

If the exhaust were blocked, I believe the turbocharger pressure would initially appear normal, but then drop off at higher RPMs. It might be beneficial to examine the cat more closely.

roorback wrote:

A charging pressure of 1 bar is requested, but it only delivers 0.4. The intake manifold and exhaust manifold are clear, the mass airflow sensor (MAF) has been replaced (I have several identical vehicles, and I've already swapped almost everything with a comparison vehicle).

1. What happens if you disconnect the control hose from the turbocharger housing? Then the wastegate should be closed, and the boost pressure should not be limited. If the LD (likely referring to a specific process parameter or substance) is still being generated in insufficient quantities, and the charger is functioning correctly with no exhaust leaks before the turbine, then the problem must be due to insufficient drive (exhaust flow).

Do you observe significant differences between the (high) average fuel consumption reading and the (lower) fuel consumption during nighttime driving? Then there's a bottleneck somewhere between the electronics and the fuel injection hardware.

Hello.

Thank you for the tips. If I disconnect the hose (which was already broken originally and probably wasn't working anyway), then the situation doesn't change much. I think if I were to adjust it, it might even produce more than 1 bar – maybe even too much... so definitely with caution. But there's nothing I can do about it.

Regarding fuel consumption, I can't say much yet, but the onboard computer shows a very low reading. I drive my commute using 4.0 liters, whereas normally I would expect something around 6 liters. That doesn't mean much to me, though, as it might be adjustable in the ESP.

Currently, it runs reasonably well up to around 3000 RPM. However, with the other control unit and chip tuning, it stops working beyond that point. It seems to me that he's getting better all the time...

I need to take a look at the exhaust – I've been thinking about how I could check it, but I can't come up with anything. Maybe I could leave the turbo completely open sometime? Would that be possible? Would you like to go for a quick drive?

I have a catalytic converter and exhaust system here, so I could swap them out. I basically have everything here, I still drive two of these cars, and I have some disassembled ones "in stock" - this makes things "cheaper" in a way, but not easier . So, I've pretty much replaced everything around and on the turbo.

Here's what I was thinking: I could install a modified LMM (lambda measurement module) and block the flap in the open position. Theoretically, this would force the software to always release the maximum fuel flow, which would likely cause excessive soot buildup, but it might work.

Otherwise, what remains is:

* Nozzles (this is quick to do, and will be next).
* ESP
* Wiring harness

Thank you all for the great help.

PS: One more question - if the intercooler had burst, you would hear it - the turbo would still spin up - and, I mean, it would be oily - so you would notice it - right? The LLK (likely referring to a specific component) is located in the package, screwed in the middle, so you can't really see it.

roorback wrote:

I need to take a look at the exhaust - I've been thinking about how I could check it, but I can't come up with anything. Maybe I could leave the turbo completely open sometime, would that be possible? And would you like to take it for a quick test drive?

As long as the exhaust gases aren't directly flowing onto heat-sensitive parts, you can try for a short time to see if it accelerates better this way.

Quote:

What I was also thinking about is installing a modified mass airflow sensor (MAF), and blocking the flap in the open position - then, theoretically, the software should always allow the full fuel flow - it would produce a lot of soot, but it should work, right?

If the MAF sensor is the cause: yes.

Quote:

If the intercooler had burst, you would hear it - the turbo would still be spinning up - and, I mean, it would be oily - so you would notice it - or not? The LLK

is actually installed in the middle of the package and is not really visible... Moreover, it should definitely whistle or make a hissing sound.
Charge air leaks can also be detected by comparing the actual charge air pressure (LD-Ist) with the actual air mass flow (LuMa-Ist), PROVIDED that both sensors are functioning correctly and the normal relationships between them are known. Unfortunately, I don't have any information about the AEL. For the 1.9 TDI engines, the ratio varies depending on the load, turbocharger, and engine speed, but it's generally in the range of 0.40 to 0.50.

"Thank you."
I'm curious to see how "quiet" the TDI will be without an exhaust.

I will report back later.

By the way, I read the link you posted earlier, but I don't understand the following:

Code:

Der für die volle Leistung erforderliche höhere Ladedruck wird erreicht, indem Ladedruck und Außendruck (von einem Abgriff im Bereich Ladereingang / Luftfilter) per Magnetventil im Schlauchsystem vermischt werden und der reduzierte Druck an die Membrandose geleitet wird. Dadurch öffnet das Wastegate erst bei entsprechend höherem Ladedruck.

The wastegate opens at 0.6 bar and limits the boost to 0.6 bar. That's exactly my desired boost pressure. How does the solenoid valve (which one?) work to achieve the required pressure? Perhaps the problem lies here...?

"Thank you!"

roorback wrote:

The wastegate opens at 0.6 bar and limits the pressure to 0.6 bar. That's exactly my desired boost pressure. How does the solenoid valve (which one?) work to achieve the required pressure? Possibly, the problem lies here...

You can find the valve by tracing the thin pressure hose from the charge air cooler backwards.

However, if the problem persists even without the pressure hose connected to the turbocharger, the valve can be ruled out as the cause, because in that case, the wastegate should not open.

Okay, that's the golden valve. Thank you.

Quote:

The controlled wastegate turbocharger (e.g., in the 1Z) has a conventional pressure-actuated diaphragm, which operates at At approximately 0.6 bar, the wastegate opens and prevents a further increase in boost pressure. The higher boost pressure required for full performance is achieved by combining boost pressure with ambient pressure (from a...). The air intake/air filter area has a solenoid valve in the hose system that mixes in the air. The reduced pressure is directed to the membrane chamber. As a result, the wastegate only opens at a correspondingly higher boost pressure.

Source: /viewtopic.php?t=3101

Hose disconnected from the wastegate -> maximum boost pressure of 0.6 bar is possible. If less boost is achieved, it could be due to the wastegate not closing properly, the turbocharger not having enough "power" (due to insufficient fuel injection), or a leak in the intake system. A popular location for drilling a hole is the underside of the 90-degree rubber elbow, directly adjacent to the intake manifold.

If the wastegate hose is connected directly to the pressure side of the turbocharger, bypassing the boost control valve (if you're unsure where that is, follow the hoses), the wastegate will remain closed, and the boost pressure will become too high. Please proceed with the test drive very cautiously and monitor the boost pressure.

Best regards, Rainer.

Hello.

I've read it, but I don't understand it because it's contradictory.
I assumed that the pressure sensor for the wastegate opens under pressure – "open" for me means bypass, which implies lower boost pressure.

So, if I disconnect the cable, there will be no pressure, the wastegate will remain closed, and the boost pressure should be fully present.
When I build boost, the wastegate opens, which reduces the boost pressure.

There are also chargers, but in that case, it's the opposite - they operate using negative pressure.

Where is my flaw in reasoning?

"Thank you!"

best regards, uwe

Quote:

I have read it, but I don't understand it because it is contradictory. I assumed that the pressure sensor for the wastegate opens under pressure – "open" for me means bypass, which implies lower boost pressure. So, if I disconnect the cable, there will be no pressure, the wastegate will remain closed, and the boost pressure should be fully present. If I build up pressure, then the wastegate is open, and the boost pressure is reduced.

Not exactly. The pressure generated by the turbocharger (hence the connection on the pressure side) is additionally added to the ambient air pressure and directed to the diaphragm of the wastegate via the solenoid valve, so that it remains.
If no pressure is applied to the wastegate valve, it will open automatically starting at approximately 0.6 bar of boost pressure, as the exhaust gases will then push against the wastegate.

Best regards, Rainer.