ATD: Slight vibration @constant 1000-1500 RPM

Hello,

Specifically when driving through town or behind trucks, if the engine speed drops below 1500 RPM in 5th gear and a constant, slightly lower speed (1000-1500 RPM) is maintained, I experience a slight jerkiness in my ATD. However, if I take my foot off the accelerator (decelerate) or give it a gentle touch, the jerkiness disappears immediately, and I can smoothly accelerate from idle speed.

I also experience this jerkiness in 4th gear, but it's not as noticeable.

For the car (Fabia TDI, 74kW, ATD)
96tkm
AGR panel (intake paths visually clean)
Coolant temperature sensor in diesel system
Timing belt/timing chain was mechanically inspected and adjusted approximately 2 weeks ago (replaced @81tkm)
All filters are approximately 15tkm old
Oil (50601) has been in since the end of January and has been used for 15tkm since then

The jerking has been present since I purchased the car (15tkm). The dealer initially filled 50500 10W40 incorrectly during "customer service", which was then replaced with 50601 after 1tkm.

A phone call with the owner did not lead to a solution - he didn't notice the shaking.

Otherwise, the car runs perfectly, starts on the first turn and immediately adjusts to idle speed. The performance is also correct, 4250 RPM in 5th gear; the DZR confirms 114 HP. However, the engine noise becomes slightly rougher at speeds above 4000 RPM.

Could one of the PD (Power Drive) elements have been damaged due to improper use with the wrong oil from the start (approximately 1200km, even under full load)? If so, how can this be checked?

Does the AGR (Exhaust Gas Recirculation) monitoring rate still play a role if the AGR is defective?

I have a 1-year (starting January 2004) warranty on the engine/transmission from the dealer (independent), but I don't want to hand the car over without precise instructions, as I've had enough of the oil issue....

[Translating...]

Hi,

ungleuich arbeitende PD Elemnte können sochle Ruckelerscheinungne natürlich zu Tage bringen, aber dafür ist der ein bisschen jung.

Was sagt denn die Leerlaufruheregelung?

[Translating...]

Bertil wrote:

Hi, ungleuich arbeitende PD Elemnte können sochle Ruckelerscheinungne natürlich zu Tage bringen, aber dafür ist der ein bisschen jung. Was sagt denn die Leerlaufruheregelung?

Mangels eines OBD2 Adapters kann ich über die Messwertgruppe 13 soviel sagen wie über das Wetter nächste Woche ....

Kann mich noch dumpf erinnern beim Freundlichen mal die Werte gesehen zu haben - waren durchweg alle optimal. 100% sicher bin ich mir im speziellen aber nicht.

Wäre es möglich, dass eines der PDE durch den Betreib mit nicht freigegebenem Öl einen mitbekommen hat? Ich fahre täglich an einem BOSCH Service Point (Diesel Service) vorbei - wäre das vielleicht eine Möglichkeit Klarheit zu schaffen?

Alternative Gedanken?

LLRR werde ich bei Gelegenheit mal unter die Lupe nehmen.