Hello,
After having read numerous threads on various forums about the TDI engine's rough running issue, here's my 10-cent worth of knowledge and my approach to solving the VW TDI rough running problem.
Because I think I should also contribute here, as the forum was so helpful when I was getting started.
Impacts:
TDI engine stutters or hesitates during acceleration or partial load; unstable idle. No check engine light (i.e. (MOT) possible.
Options:
According to forums, some customers had to replace almost everything in their cars. This included the air mass flow sensor, pedal position sensor, and even the ESP. I experienced anxiety sweat while watching the plays described. (My vehicle diagnostics also gave me nonsensical information: "Pedal position sensor defective, value blablabla...")
Often, exchanging expensive replacement parts or even the entire fuel injection pump is unnecessary. (My research: Original price 2700.- / Replacement 1600.- / Bosch cleaning+ installation probably around 600-800.- (assuming that the relevant Bosch Car Service even has a diesel test bench))
Solution
As it appears, cleaning the volume stacker (the upper part of the ESP) helps in 80-90% of cases. There is also a relevant, illustrated technical article/download available in the forum, which is causing great excitement among experts.
This does not require a complete expansion of the ESP. The work can even be carried out by one or two people in the engine compartment, even with integrated mass flow meters. However, it seems that removing [EDIT: the MSW] and performing a previous data read-out with VAG-COM is the better method.
Despite using VAG-COM, I didn't initially believe I could do this myself, as it's a tight space, and I need the car frequently, so I can't afford to make any mistakes.
I have finally found a workshop that specializes in cleaning and precisely adjusting the MSW. (I am happy to provide you with the address and phone number of PSM upon request.)
In the end, I got away with it for a super cheap price of 150. ( + 50 .- fuel) Lasted 2 hours and 5 cups of coffee.
After that, I no longer had a chaotic learning process, no more disruptions, and I no longer failed in the ASU (presumably an assessment or exam). The next day, I received a perfect outfit at my GTÜ!
As a bonus, the men also informed me that my temperature sensor in the charging unit was defective, and that this was the reason why I occasionally experienced a sudden drop in performance when running at full load. With 25, that's also finished.
DIY Tip:
Simply use a hammer to split, unscrew, and discard the "triangle screw" of the MSW! Subsequently, replace it with a standard M6x60 screw!
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