TDI Smoking, Power Loss After 3km?

My TDI was emitting excessive smoke, and after about 3 km at full load, it stopped working.

Hello everyone, I'm new here, and as you might expect, a question led me through the entire internet until I ended up here .
I have a 3-door Golf TDI 1.9 with the standard 90 horsepower, and it has 217,000 kilometers. For some time now, it has been producing a lot of smoke from the exhaust when under full load. (I've replaced the air and diesel filters, cleaned the pump, and added an additive, but there's no improvement!) Since I don't often drive in situations where I need full power, I'm not too concerned, but the emissions test is failing. The car is significantly above the acceptable limits, and contrary to all expectations, it's getting worse with each full-load test .
'In my previous 2.0 TDI, I had a similar problem, which I solved quickly by turning the full load quantity adjustment screw on the injection pump quite a bit... I then drove, with full throttle, so around 90 km/h, to the inspection , but always had good values, and no one noticed. Is this also possible with a TDI? I have VAG-COM available as a tool.'
Okay, there's something I should mention. After driving for a longer period, say about 3-4 kilometers at full throttle, the bike simply cuts out, as if it's not getting any fuel. Then, after a short, leisurely ride of about 100-200 meters, it starts up again without any unusual noises or anything like that. Besides the fuel filter in the engine compartment, is there another one that could be the problem? I'm completely baffled by this. The error memory is empty, so there are no recorded errors. Does anyone have any ideas, whether it's a way to trick the inspection or to fix the underlying cause?
Okay, one more thing, the fuel line seems to be fine, so I'm less likely to think he's drawing air through it (because of the full load issue). Also, the engine actually runs very smoothly, even immediately before and after one of these described failures. He also doesn't have any starting problems.
Okay, so thank you in advance for the, hopefully many, answers .

Bye, Birger.

Hi there,

'Your problem doesn't sound like a fuel supply issue, but more like insufficient boost pressure. That's probably why you're seeing soot. Eventually, the injection quantity will be reduced to compensate, which you'll experience as a loss of power. Could you log the boost pressure values using VAG-COM and post them? Or do you have a lambda sensor (O2 sensor) installed?'

'Also, the MKB (German Central Product Classification) would also be quite interesting. Otherwise, it will be like fortune-telling!'
In my opinion, there should still be something stored in the error memory, or perhaps the preheating indicator might flash if you notice a loss of power.

MKB can only be 1Z, AHU, or ALE.

And they are virtually identical, with only minimal differences.

AHU has the long flexible duct.
ALE uses 220 bar nozzles due to EURO3 regulations.

m;

CLICK

CLICK

CU Gremlin.

Hi, it's great how smoothly things are going. Just to preface this, I'm not an expert in this field, but that doesn't mean I'm stupid or don't have any understanding of the subject matter. It's possible that I might not understand some of the abbreviations, but that doesn't mean I don't understand the technology itself. MKB... I hope that's the engine code, and it's 1Z.
The boost pressure is fine; it settles at 1846 mb under full load. I can gladly upload a log file online, but unfortunately, I'm not at home right now. Since I use T-Online, I only have access to my website through my account, but I can do that tomorrow. Here's a short excerpt to avoid overwhelming you with numbers.
304.90,2016,1285,1071,77.3,,,,,,,,,,
305.28, 1995, 1714, 1122, 36.3, , , , , , , , , , ,
305.67, 2016, 1877, 1255, 35.9, , , , , , , , , , ,
306.05, 2058, 1877, 1499, 35.9, , , , , , , , , , ,
306.43, 2100, 1877, 1693, 35.9, , , , , , , , , , , ,
306.82, 2142, 1877, 1805, 35.1, , , , , , , , , , ,
,307.20,2163,1877,1877,36.3,,,,,,,,,,
307.59, 2205, 1867, 1918, 39.0, , , , , , , , , , ,
307.99, 2247, 1867, 1948, 42.6, , , , , , , , , , ,
308.37, 2289, 1867, 1958, 46.6, , , , , , , , , , ,
308.76, 2310, 1867, 1969, 51.0, , , , , , , , , , ,
,309.14,2352,1856,1979,57.0,,,,,,,,,,
,309.53,2394,1856,1989,64.1,,,,,,,,,,
,309.91,2436,1856,1999,72.1,,,,,,,,,,
,310.29,2457,1856,1969,77.7,,,,,,,,,,
,310.68,2499,1846,1928,80.9,,,,,,,,,,
311.06, 2541, 1846, 1907, 82.9, , , , , , , , , , ,
,311.45,2583,1846,1856,82.9,,,,,,,,,,
,311.89,2604,1846,1826,81.7,,,,,,,,,,
,312.27,2646,1846,1856,82.9,,,,,,,,,,
,312.65,2667,1846,1867,83.3,,,,,,,,,,
313.04, 2709, 1846, 1856, 83.7, , , , , , , , , , ,
,313.48,2751,1846,1856,83.7,,,,,,,,,,
,313.86,2772,1846,1836,82.9,,,,,,,,,,
,314.25,2814,1846,1846,83.3,,,,,,,,,,

golf3tdi wrote:

The boost pressure is fine; it settles at 1846 mb under full load.

. . . remain the "classic TDI soot producers," known as.
-> Vacuum leak / Low-pressure coolant leak between the turbocharger and the engine.
-> non-closing AGR valve...

I couldn't hear any hissing , so I always remove the thick body plug located behind the fuse and relay panel, which allows me to better perceive any sounds. Visually, I couldn't detect any leaks in the lines or on the radiator itself, although the radiator is somewhat hidden and I couldn't inspect it completely. If there were a leak, the leak point should be 'sweating'. I might eventually unscrew the lines and blow air through them }, or is there a more elegant method?
AGR valve...
Is that the valve that, in case of a malfunction of the turbocharger pressure regulator, essentially opens a bypass and thus protects the engine from excessive boost pressure? Sorry, as I said, I don't know all the abbreviations, since I'm not a car mechanic; I became an industrial mechanic instead, but ever since I was a kid, I've always fixed everything on my car myself, no modifications, just repairs, but I do everything myself.
Okay, besides the issue of the engine failing under full load, how can I reduce the turbidity level if I can't find any other problems and the engine is simply worn out? 217,000 km is quite a lot of mileage, after all... Well, the emissions test has expired and wasn't passed.

AGR stands for "Abgasrückführung," which is the component that recirculates exhaust gases back into the engine, especially during partial load conditions, to reduce emissions. It should close during full load to ensure the engine receives 100% fresh air. However, due to carbon buildup, the valve may eventually fail to seal properly.
It explains how to put an end to it.
/viewtopic.php?t=3095&highlight=abgasr%FCckf%FChrung

Here's some information about increasing the fuel injection amount. Maybe you can use this to slightly reduce your fuel quantity. It might not be much, but it could be exactly what's missing.
/viewtopic.php?t=1094&highlight=adaption+tuning

Hello,

The AGR valve is the exhaust gas recirculation valve. Its functionality is very well described in the technical articles. You can find it on the homepage under 'Technical Articles' --> 'General' --> 'Function of Exhaust Gas Recirculation.' It describes everything from its functionality to problems and troubleshooting, even including issues caused by 'accidentally installed metal plates.'

The articles also contain a wealth of other interesting information: functional descriptions, troubleshooting guides, common errors, procedures for troubleshooting using VAG-COM, and more.

In simple terms: In the partial load range, the engine 'feeds' its own exhaust gases back into the intake. At full throttle, this valve should be closed to prevent this from happening. Otherwise: Lack of oxygen --> soot = excessive opacity.

To cause a TDI engine with 217,000 km (approximately 135,000 miles) to fail the emissions test requires significant neglect and abuse. Typically, TDI engines can still pass the emissions test even with 400,000 km (approximately 249,000 miles). While TDIs have some common problems, they are generally very durable and can last a very long time, as long as these common issues are regularly checked and addressed.

Regards,
Private.

EDIT: mcgyver2k was faster...

'Thank you for the great tips. At least now I have a starting point, because the test showed that in the basic setting mode of the mass airflow sensor block 003, the air mass remained stuck at a value, ignoring minor fluctuations. The value was approximately 360 mg/stroke ±15. If the air mass values remain constant, then the valve is probably stuck... or it's not being activated at all. If the mass airflow values are correct, then, according to the values in the report about the EGR valve, it would be stuck in an open position. So, I'll take a look at that. Also, is it possible to get the valve working again if it gets clogged, or should I just buy a new one? The part doesn't look very repair-friendly. It could also be that the membranes are broken... I guess I just have to take a look. I'm assuming that the mass airflow sensor is still measuring something reasonably accurate, at least I'm getting different values while driving (see log file). At idle, the value is also within the target range of your target value table, but there's a difference of about 100-120 mg/stroke compared to the target value in VAG-COM (see log file beginning).'
Okay, I've now also added the two log files, measurement block 003 and 011, to my HP area - http://home.t-online.de/home/Birger.Hahn/temp_daten/ - for anyone who wants to take a look. You can see there that the mass airflow sensor is at least still capable of capturing different values.
Furthermore, I noticed in the TDI graph that my fuel injection timing is 'slightly delayed.' This could also be considered as an additional factor. The fuel temperature was approximately 150, and the injection timing fluctuated between 30 and 35. VAGCOM reported the message 'slightly delayed' in this regard.

Topic: DPF Repair.
Hier im Forum herrscht die einhellige Meinung, daß das Ding fast nur Schaden anrichtet (durch Ausfälle und durch Verdrecken des Ansaugweges) und wenig nutzt. Daher wird es von vielen auch schon bei korrekter Funktion deaktiviert. SSame here.

The technical article about the AGR also describes how to do it (by inserting a piece of metal).

You should at least try that first; then you can rule out any influence from the AGR (Abgasrückführung).

Regards,
Private.

I could do that, but what about the MOT (vehicle inspection)? The EGR system is there to make the values look a little better. So, I'm only doing this whole thing because I didn't pass the } MOT... Well, with these prices, I don't want to start too many attempts. But I've also noticed that the EGR system isn't exactly considered a friend of TDI owners }.

No, the EGR system mainly reduces NOx emissions. These are not measured during the vehicle inspection.

'On the other hand, the level of turbidity is definitely better without the use of agricultural runoff.'


CU Gremlin.