Fuel Injector Replacement: PD Wear & Issues

To all VAG specialists:

When would you replace the injectors? Based on what mileage, or what engine behavior (e.g., smoking, hard combustion, etc.)?
What is the probability that a piston will melt if a nozzle fails?
I'm specifically interested in information related to the 96kW PD TDI (AWX) engine.

P.S.: On what basis does DI Kaufmann recommend the 160,000 km as the mileage for the exchange?

Quote:

P.S.: On what basis are the 160,000 km that DI Kaufmann recommends for the trade-in based?

Empirical values

http://shop.dieselschrauber.de/duesen_neu.html

And the next person who comes along with a 15mm wrench and says "everything's easy" can just go away.
I had a car in here just yesterday, with an idle speed control value of 3.xx mg/stroke in the MWB13, resulting in a terrible idle.

"I'm asking here in the forum because I don't have any prior experience. It's not polite to directly ask someone for help. Answers like "they won't break" are not helpful to me. I definitely won't be replacing the injectors myself... If faulty injectors announce themselves through the engine's idle, that's a good thing. I can understand that."

"Do all nozzles that have run 190,000 km look like that? You can't really influence the wear of the hydroelements. I'm surprised that the pressure elements aren't replaced more often, or that they don't need to be."

Hello,

No, of course not. The "worthwhile point" is meant to be around 160,000 km. There are also injectors with over 200,000 km that still atomize well, but they have still deviated from the correct opening pressure. It depends heavily on how the kilometers were accumulated (fuel quantity) and what fuel was used.

Best regards, Rainer.

Hello,

Is the MWB 13 value in this context informative enough to determine the extent of wear and tear on the PD components?

My engine has now reached 250,000 km, and the readings are fluctuating by +/- 0.4 for all four cylinders.

My readings are also around +/- 0.4, but one cylinder is performing worse. Cylinder 4 is in the positive range. It's not uncommon to see that the fourth cylinder is weaker, for whatever reason.

Hi,

The MWB13 is a good indicator of when it's crucial to check if the PD units/nozzles are worn out or if there are other issues (such as piston rings, valves, or cylinder bores).
If all injectors wear out uniformly at random, you won't notice anything unusual in the MWB13, although atomization and fuel consumption will be suboptimal.

Appropriate testing equipment for PD (partial discharge) elements is being prepared and will be available in the medium term. However, the PD elements will need to be removed for this testing.

Best regards, Rainer.

Rainer K. wrote:

If all injectors wear out uniformly at random, you won't notice anything unusual in the MWB13, although atomization and fuel consumption will be suboptimal.

It's similar to my idle stabilization system (although I don't have a PD). I had worn-out injectors, broken hydraulic lifters, poorly atomizing injectors, and too low opening pressures. Nevertheless, it was a 100% functional idle stabilization system (something even a new engine would dream of). This idle stabilization system is also used as an indicator, although it is sometimes completely useless. In my case, everything was simply worn out evenly.

Does this mean that the values in MWB13 don't change significantly with increased wear? If the nozzles wear down evenly, is monitoring MWB13 pointless?

Okay, if everyone is equally good or equally bad, you won't notice any differences in MWB13.

Okay, here's the translation:

"Just a silly question: Is the specific impulse (Isp) of the MWB 13 engine measured in a hot or cold state?"
When it's cold, it also runs above or below the target values.

Alukugel wrote:

Once again, a silly question: Is the MWB 13 measured in a warm or cold state?! If it's cold, it also runs above or below the target values.

The values should be within the tolerance range when the engine is both cold and warm.

Best regards, Rainer.

Okay, so off to Audi to get 3 new nozzles under warranty , but the MWB 23?! So, the one for the electric control only goes down to -41, so those should still be okay. The next thing is that when you press the clutch, the values go back into the target range...