Help - Golf Plus 105 hp TDI is shaking/jerking

Hello everyone,

My 1.9L, 77kW, 105 HP TDI Golf Plus (built in 07/2006, engine code: BLS) has been experiencing rough running for the past three weeks.

There's a slight stuttering, and a more pronounced stuttering, which I'd like to describe here.

Here are the facts that apply to both types of stuttering:
- The engine misfires when it's cold and when it's warm.
- the outside temperature seems to be irrelevant.
- Filling the tank (full or almost empty) with Aral or Shell regular diesel has no effect.
- Never used biodiesel or anything like that.
- The car has a DPF (Diesel Particulate Filter).
- The vehicle accelerates linearly, meaning that when starting in first gear, there is no sudden surge of power at approximately 2200 RPM.
- The car reaches a top speed of 190 km/h.
- The car does NOT jerk when you lift your foot off the accelerator, and it doesn't jerk even when accelerating very strongly.
- No indication whatsoever on the instrument cluster or the MFA plus display.
- No data in the error memory.
- Jerky movement across all RPM ranges, often when "maintaining speed."
- Same behavior with cruise control.

Slight stuttering:
- Stuttering is present when "maintaining speed," during transitions between thrust and reverse thrust, and at extremely minimal acceleration.
- It feels like the car momentarily stops accelerating.
- Where there used to be a noticeable boost in power three weeks ago, I sometimes feel like it momentarily dips before continuing to accelerate linearly.

Severe jolting.
- The stuttering is very noticeable.
- There is stuttering when "maintaining speed," and there is a switch between thrust and pull.
- The jerking is now noticeable even with slightly stronger acceleration (but not when pressing the accelerator pedal all the way down).
- The gas pedal reacts with a delay, meaning I press it – nothing happens – and then, after about 1 second, it delivers full power corresponding to the position of the gas pedal. So, there's no gradual increase in power, but an immediate jump to the selected gas pedal position. This causes a noticeable jolt!

The strong jolting has occurred three times in the last two weeks. Once, restarting the engine helped, and another time, the jolting disappeared after about 10 minutes.
Heute bin ich mit starkem Ruckeln in die Werkstatt, ohne Motor an/aus sofort Diagnosecomputer dran, alle Steuergeräte OK. Kein Fehler. Dann Probefahrt und es war bis auf ein paar etwas stärkere Ruckler ehr ein leichtes Ruckeln. EUnfortunately, it seems to be cursed.

I then got back on the highway, accelerated to full speed a few times, but without any change.

As I said, there were no error codes stored (3 times). Due to the delay, the accelerator pedal was replaced. No change. The turbine-like noise from the turbocharger remains unchanged.

Since the lack of turbo boost and the stuttering occurred simultaneously, I think that restoring the turbo boost will also resolve the stuttering. But where did the turbo boost go? The essential data blocks have been checked, and everything seems plausible.

"Does anyone have any ideas? What could it be, or how can we narrow down the problem? And where is the turbo boost going?"

I hope for your help!

Thank you very much.

Regards,
Tobias.

Hello Tobias,

After checking the error memory and finding nothing, I would rather look for the problem "elsewhere" or "in a less obvious place".

Have you ever checked the exhaust gas recirculation valve?

I also once experienced a similar strange behavior in partial load operation, as if the accelerator was being released and then pressed again repeatedly.

The AGR (Abgasrückführung - exhaust gas recirculation) valve was completely clogged with soot, which significantly reduced the cross-section of the intake manifold and, consequently, the engine's power output.

What does the boost pressure do?
It would be good to log data from idle speed to full RPM.


Regards,
Werner.

Hello,
What software was used for the data retrieval, and is there an automatic scan function?
Please observe the forum rules. We do not provide support without a support key or a valid "Dieselschrauber" customer status.
Best regards,

Quote:

Hast du schon mal das Abgasrückführungsventil angeschaut?

Hi,
Have you checked the date yet?
Will there still be a need for support after 10 years?

Best regards from Berlin,
olli

olli wrote:

Hi, Have you checked the date yet? Ob da nach 10 Jahren noch Bedarf an Support besteht...

Ohhhh, that's a typical beginner's mistake. I think there's really no need for that anymore.
Thank you for the hint .