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Touareg 2.5 TDi Idle Speed

 
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Kevgo24



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Post28-11-2023, 18:47    Subject: Touareg 2.5 TDi Idle Speed Quote

Good evening, everyone.

Here's a problem I'm having with my Touareg.

The engine was replaced a few months ago, but I unfortunately don't know where or by whom.

Idling is very unstable. Okay at 1400 RPM.

Starts immediately without any problems.

No errors found.

BAC Motor 2.5 TDI 2005.


Here are the values for vcds.

Two power drive elements (PDEs) were recently replaced, specifically cylinders 2 and 5.



PXL_20231128_163312522.jpg
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 Touareg 2.5 TDi Idle Speed
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PXL_20231128_163312522.jpg


PXL_20231128_163250452.jpg
 Description:
 Touareg 2.5 TDi Idle Speed
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PXL_20231128_163250452.jpg



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Post28-11-2023, 19:16    Subject: Touareg 2.5 TDi Idle Speed Quote

Hello,

The BAC must be a pump-nozzle engine.
Does he achieve full performance in that way?

If so, I would first check the correct alignment and installation of the valve lifters and camshaft/rocker arm shaft.

Only after everything else has been checked and appears normal should a compression test be considered.

Best regards, Rainer.


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Kevgo24



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Post28-11-2023, 19:59    Subject: Touareg 2.5 TDi Idle Speed Quote

Thank you very much.

Yes, it is a pump-injector engine.

I just adjusted the settings again, but there's no difference.

Tomorrow, I will double-check the PDE wiring harness. Otherwise, it seems we really need to measure the compression.


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dieselschrauber
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Post28-11-2023, 20:17    Subject: Touareg 2.5 TDi Idle Speed Quote

Please also consider the copper sealing washers icon_wink.gif located below the injector nozzles of the PD (piezoelectric) elements in the cylinder head , as I have already encountered cases where either none were installed or two were stacked on top of each other .


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Kevgo24



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Post28-11-2023, 20:24    Subject: Touareg 2.5 TDi Idle Speed Quote

I had all the PD elements outside and resealed them, because I had encountered a similar issue before. icon_biggrin.gif

Shouldn't the high variations in switching times indicate a fuel shortage? I seem to recall reading something about that; do you know anything about it?


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Post28-11-2023, 20:40    Subject: Touareg 2.5 TDi Idle Speed Quote

Kevgo24 wrote:
I had removed all the PD elements and resealed them, as I had encountered a similar issue before. icon_biggrin.gif

icon_lol.gif

Kevgo24 wrote:
Shouldn't the high switching time variations indicate a lack of fuel? I read something about that once, do you know anything about it?

Good question, there's no unit attached, I suspect it's US. icon_biggrin.gif
Sorry, I don't have any specific values in mind right now, but comparison values should be available in various threads within this forum.


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dieselschrauber
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Post28-11-2023, 20:43    Subject: Touareg 2.5 TDi Idle Speed Quote

Okay, I understand. Please provide the German text you want me to translate into English. I will only provide the translation.

Have you already measured the pre-charge pressure of the tandem pump?


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Kevgo24



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Post29-11-2023, 23:19    Subject: Touareg 2.5 TDi Idle Speed Quote

Hi. So, I looked at the wiring harness again today and couldn't find anything wrong.

Bleed the new diesel filter, everything. Okay. It also starts up perfectly. The engine is running a little better, but it's still very rough.

The pump was inspected and is in good condition according to Volkswagen standards.


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Post30-11-2023, 12:03    Subject: Touareg 2.5 TDi Idle Speed Quote

Hello,

Is there pressure on the tandem pump? Is there definitely enough diesel coming from the rear? Does it run under load, or does it stall? Is the PFE wiring harness okay? Are the PDE settings configured correctly?

Generally, the LLR (Load Limit Regulation) is operating at its maximum capacity in the 4 PDE (presumably a specific system or process).

Best regards.
Manfred.
Golf V 2.0 TDI - 4motion (BKD) im Ruhezustand mit >500Tkm
Golf 7 Alltrack - 4motion (DGCA)
Passat Alltrack - 4motion (CFGC)
Touareg V10 TDI (AYH)


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Kevgo24



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Post30-11-2023, 13:55    Subject: Touareg 2.5 TDi Idle Speed Quote

Yes, the PDE settings are definitely correct.

Yes, there's plenty coming from the back!

I haven't looked any further into the tandem pump itself yet.


I will replace the wiring harness again tomorrow with the old one, and I'll get back to you then.


It just makes me curious that the values are changing to zero. Cylinder 1, for example, has even better values after the diesel filter change and is at 0.


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Kevgo24



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Post10-12-2023, 17:21    Subject: Touareg 2.5 TDi Idle Speed Quote

Hello everyone,

It was the wiring harness that was defective.

Sure, here's the translation:

"MFG Kevgo" translates to "Best regards, Kevgo" or "Sincerely, Kevgo" in English. It's a common way to sign off an email or letter.


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Post10-12-2023, 18:56    Subject: Touareg 2.5 TDi Idle Speed Quote

Thank you for the feedback! icon_smile_thumb_up.gif


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