Golf 4 TDI: Jerking/Hesitation at 2000-3000 RPM and under full load

Hello,

We've been experiencing a shaking or jerking issue in our Golf 4 TDI Variant for quite some time, specifically between 2000-3000 RPM and under full load.

LMM and AGR have already been replaced! Could it be the PDE?

I've uploaded a LOG file containing data from MSB 13-18 and 23.
Here is the link to it: /viewtopic.php?t=20889

Okay, I can't really make sense of the values that are being displayed.

I hope you can help me; we've been struggling with this problem for a long time.

Best regards,
Chris.

Hello.

Quote:

also ich kann bei den angezeigten werten nicht wirklich was erkennen!

tja also ich auch. Sind auch die falschen MWB.

Wie schon oft zu lesen hier die 3, 8, 11 loggen und wenn es geht von ca:1000U/min - 4000U/min mit Vollgas ohne unterbrechung. Am besten gehts im 3. Okay.


Regards,

Please also include the horsepower (PS), engine displacement (MKB), mileage, and year of manufacture.

@charlyfirpro
I don't know what problem you're having. MWB13, 18, and 23 should fit...

@eiki
It could also be due to the ZMS. How many kilometers has the car been driven?
What exact engine do you have?

Hello,

It's a 1.9 TDI engine with 115 hp (116 hp?). I don't remember the exact engine code off the top of my head right now!

It currently has 152,000 kilometers on the odometer.

What are MSB 3, 8, and 11? And what does that have to do with the ZMS? Does a new one need to be installed?

I also have some new log files:



/viewtopic.php?p=147211#147211

Regards,
Chris.

Hello.

Quote:

@charlyfirpro I don't know what problem you're having. MWB13, 18, and 23 should fit...

I don't know what one is supposed to see there.

MWB 13 might be interesting. It seems okay so far. I can't assess MWB 18 because the speed is missing.

Simply log 3, 8, and 11 out of 1000-4000 RPM when at full throttle.

A dual-mass flywheel (ZMS) is always a potential culprit, but before replacing it, I always check the simpler, more common issues first.

Quote:

Does a new one need to be put in then?

Yes, it should! Unless you're absolutely sure that the used item is in good condition.

Best regards,

Hello,

I will now log MWB 3, 8, and 11.

I will post the values here again when I have them!

Thanks again for your help.

Regards,
Chris.

That would be an AJM, then?
Does it also have the PDE wiring harness?
Would you hit it?

Hello,

Okay, here are the logs from MWB 3, 8, and 11!

/viewtopic.php?t=20912

Regards,
Chris.

Hello.

Well, that was almost nothing. It's barely running at full throttle and not reaching 4000 RPM.

I've noticed a few inconsistencies that might not be right. However, you need a reliable log to investigate this properly.


I'll explain it again.
Find a road with little or no traffic (e.g., a straight road in an industrial area, perhaps in the evening).
Then, in 3rd gear, approximately 1000 RPM --> Start the logging. Full throttle to 4000 RPM without interruption.
Stop the log and insert it here.


Kabelbaum der PDe. Ja sicher auch ein Kandidat. Aber besser und Preiswerter ist sicher ein Log vorher auszuwerten. Or?

Best regards,

Hello.

Here's a new log with speeds ranging from 1000 to 4000 RPM.

/viewtopic.php?p=147349#147349

Sorry that the previous translation wasn't quite right.

Regards,
Chris.

Hello.

The log was very good this time. Question: Did the stuttering occur while creating the log? Or was it not noticeable there?
Is it always the case, or only when the engine is warm? Or does it only happen after driving for a longer period?

Overall, the log looks good. I assume there are no memory errors, or that there were none.

In your previous logs, the idle speed control seemed to be working correctly. I'll disable the P drive for now.

Please check the wiring harness of the PDe for any breaks or loose connections.
Here in the forum, there's a guide written by a member that explains how to check the ZMS (presumably a software or system).
Try using the search function. (I'm not exactly sure how it works.)

Best regards,

Yes, the jerking also occurred in that log, but only quite late and at a high RPM, around 3500 RPM.

The shaking is actually always there! It's especially noticeable when driving uphill.

Okay, there were no errors in the error memory.

I've already checked the ZMS, and it seems to be working fine!

I'll check the PDE wiring harness sometime in the next few days.

Thank you in advance for your help!

Regards,
Chris.

Don't test it, just replace it. You won't be able to tell if it's okay or not, so just replace it, please! It's going to be very brittle, the contacts are no longer good, the connections are bad. It's pointless to leave that old part in there; it's a worthwhile investment of 50€.

charlyfirpo wrote:

Hello. In your previous logs, the idle speed control seemed to be working correctly. I'll disable the P drive for now.

Appropriate LLR compensation values are not a reason to exclude the injectors.

Quote:

Please check the wiring harness of the PDe for any breaks or loose connections.

Go for it.
The causes of the jerking could also be related to fuel supply or fuel temperature. You could try replacing a section of the diesel line with a transparent one and check for air bubbles. Is the fuel filter being replaced at the recommended interval? Is the filter in the fuel pre-filter clean? What does the fuel temperature reading show on the MWB7 when the engine is warm?
You can also measure the pressure of the tandem pump (have it measured). VAG tools are required. During this measurement, you can also feel the play in the high-pressure pump's pressure relief valve.

Quote:

Here in the forum, there's a guide written by a member that explains how to check the ZMS (presumably a software or system). Try using the search function. (I'm not exactly sure how it works.)

The member's name is Ulf, and you should use "Hoppeltest" as the search term.