Reduce MSW: Disassemble or Lower Injection Amount

Hello!
"My Golf TDI 1Z / 66kW with 300,000 km has been experiencing a lot of shaking for quite some time. After the shaking, especially in the RPM range of ~1300-1-2100-1, became increasingly worse in 4th and 5th gear, but also in 3rd gear, I decided to investigate the issue."
Checking the error memory didn't help me in this case, as it was empty.
After doing some research in the forum, it turned out that the quantity control valve of the VP37 was the culprit. I disconnected the speed sensor, and the jerking stopped.
The symptoms (jerking within the specified RPM range) suggest, in my opinion, a malfunctioning or sticking MSW (Motor Slip Warning) system.
Before I started disassembling the MSW, I checked the fuel injection volume at idle. In my case, it was 2.0-2.2mg per injection. This is within the VAG specification range (2.0 - 9 mg per injection), but still outside the "recommended" value range (according to /viewtopic.php?t=658, at least 3mg, or according to /viewtopic.php?t=5517, between 4 and 5.5mg as a standard).
Now, according to /viewtopic.php?t=658, I adjusted the values with VAG-COM to 3.8mg. -> Lo and behold, the jerking became better (smoother), but it's not completely gone.
Now I'm wondering if it would be beneficial to further adjust the settings, essentially "fine-tuning" the mechanical alignment of the MSW (by shifting the pump head with the control mechanism on the pump body), or if I should disassemble and clean the MSW.
Personally, I think that cleaning up the MSW will achieve more and address the problem at its root. Am I understanding this correctly?

P.S.: Actually, I wanted to post this thread in the "Diesel - Engine Technology" section because it would be more appropriate. Maybe a moderator will move it?

After no one answered me , I quickly disassembled the MSW. Once again, a heartfelt thank you to the author of the article on disassembling the VP37!
There was so much dirt in it, I can hardly imagine that anything of the pump is still there . The jerking is completely gone now. Let's see how long this lasts...

Hello,

After having read almost every thread here and elsewhere about the jerky behavior of TDI engines, here's my two cents and my approach regarding the VW TDI "judder" problem.

Because I think I should also contribute something to the forum, especially since it helped me so much when I was just starting out.


Effects:

TDI stottert oder ruckelt beim Beschleunigen oder im Teillast; unruhiger Leerlauf. Keine ASU ( respekt. (TÜV) is possible.


Options:

According to forum posts, some customers have had almost everything replaced in workshops. From mass airflow sensors to accelerator pedal sensors and even ESP systems. I got a chill reading about the dramas described. (My vehicle's diagnostic system also incorrectly reported: "Accelerator pedal sensor defective, value blablabla...")

Often, it's not necessary to replace expensive spare parts or even the entire fuel injection pump. (My research: New price €2700 / Replacement €1600 / Bosch cleaning and installation likely around €600-800 - assuming the respective Bosch Car Service even has a diesel test bench).


Solution

It appears that cleaning the powder collection hopper (the upper part of the ESP) helps in 80-90% of cases. There is a relevant illustrated technical article/download available in the forum, which has generated a lot of enthusiasm among experienced users.

It is not necessary to completely disassemble the entire ESP system. Some people might even be able to perform the work with the quantity control unit installed in the engine compartment, but it seems that removing [EDIT: the MSW - Motorsteuergerät/Engine Control Unit] and reading the measurement data beforehand with VAG-COM is the better method.

I didn't dare to try doing this myself the first time, even with VAG-COM, because it can be tricky, and I need the car constantly, so I can't afford to make any mistakes.

After a long search, I found a workshop that specializes in cleaning and precisely calibrating the MSW. (I'm happy to provide the address and phone number upon request, PSM.)

In the end, I got away with it for a very cheap price of 150.- (plus 50.- for gas). It took 2 hours and 5 cups of coffee.

After that, I experienced no more unstable idling, no more jerking, and no more failures during the vehicle inspection. The very next day, I received a perfect result on my GTÜ inspection!

As a parting shot, the guys told me that my temperature gauge is faulty and that it's the reason I've been experiencing occasional, brief power drops under full load. Luckily, it's a cheap fix at 25 euros.



_{Tip for DIY enthusiasts:
Simply slot the "triangular screw" of the MSW with a chisel, unscrew it, and discard it!} Then replace it with a standard M6x60 screw! }

Okay, please provide the German text you would like me to translate into English. I will provide only the translation.