Interruptions in AFN broadcasts

Hello.

My search didn't yield any suitable results, so that's why I'm asking this question:

I've been driving a 1996 Passat Variant 35i with an AFN engine for a year now, and it currently has 321,000 kilometers on the odometer.

It runs smoothly except for a minor "hiccup" at around 2800 RPM.

I don't notice it in the lower gears, but it becomes unpleasant, especially under load, in the fourth or fifth gear.

He proceeds past that point as if nothing happened, according to the logs. Speedometer reading: approximately 210 km/h.

It still has the original (Pierburg) mass airflow sensor, requires very little oil, and runs like a cat.

There are no error codes stored in the memory.

Where would be a good place to start looking? I would prefer to try home remedies first, if possible.

Does anyone have any specific tips on how I can surprise a friend using a VAG tester?

Best regards, Rüdi.

If you have access to VAG-COM, that's already half the battle. Then you should take some logs and pinpoint the source of the error. I'm just speculating, but it's possible that the VTG (variable timing gear) is causing issues. You can check that relatively quickly and easily with some simple home methods. The rest is probably more difficult, as it seems like there aren't any major, persistent problems, like a potential leak in the charge air system.

At 321,000 km, having a VAG COM diagnostic tool is definitely a good idea if you plan to put on even more kilometers!

Hello!

I'm very familiar with the Hakler at 2800 RPM; according to my VAG-COM scan, that's what I'm experiencing.
a undershoot following a correction of an overshoot, likely also due to [something].
a slightly awkward vintage car.

Measurement with groups 3-8-11, full-throttle acceleration in 3rd, 4th, and 5th gear. Speed from 1500 RPM.

Regards, Klaus.

VW Golf III, AFN engine, 165,000 km.

I also experienced the same issue, but the fluctuation in RPM was between 2800 and 3500 RPM.

I read the MSW and found an error. The mass flow meter (LMM) occasionally dropped to approximately 500 mg and then rose again to 1100 mg. It feels like someone is turning the fuel off and on again.

Hello!

@Steffarn

Quote:

I read the MSW and found errors. The LMM intermittently dropped to approximately 500mg and then rose again to 1100mg. It feels like someone is turning the fuel off and on again.

Does "Error found" mean that you confirmed the behavior in the measurement data?
or it states that there was actually a defect in the LMM (lambda measurement module), and the problem was resolved with a new LMM.
was was gone?

If the VTG (Variable Transmission Gear) is stuttering, and reducing the load (LD) "suddenly" works, then...
When a underswing occurs, a nearly simultaneous drop in the mass flow rate (MFR) is observed.
It's only logical.

With the new mass airflow sensor (installed six months ago), the mass airflow values have indeed increased.
However, the dip in performance during the seemingly "problematic" process of scaling down remains.

Regards, Klaus.

Please provide the German text you would like me to translate into English.

VW Golf III, AFN engine, 165,000 km.