VCDS and OBD diagnostic device in the On-Board Diagnostics Shop
Diesel, Engine Technology and Vehicle Technology. Repair, Maintenance and Diagnostics (OBD).

TDI Catalytic Converter Replacement

 
New Topic Reply 🔗 ⭐ 🖨 Dieselschrauber - Index » Diesel Engine Technology
Author Message
roorback
Blaumann
Blaumann


Joined: 12/22/2003
Posts: 374
Karma: +1 / -2   Thank you, like it!
Location: kärnten/österreich

Free account, no CAN development support

Post08-05-2009, 19:50    Subject: TDI Catalytic Converter Replacement Quote

hello

I've now heard twice that people are removing the catalytic converter on TDI vehicles.

Now, I'd like to know if this actually achieves anything, and if so, what exactly does it accomplish?

I theoretically have the possibility of testing this with a second system from Schlachter.

I have no idea what to expect from this.

I'm curious to see.

best regards, uwe
volvo 850 tdi - 2.5l AEL aut. bj.96 - bald 500000km
volvo v70n 2.4 - 2.5l 5Zyl Sauger bj. 2005


Translated on 04-10-2026, 6:06.
Back to top Profile PM
TDI-GTI-4-Motion
Profi-Schrauber
Profi-Schrauber
Avatar-TDI-GTI-4-Motion

Joined: 02/22/2009
Posts: 3865
Karma: +127 / -0   Thank you, like it!

2002 Volkswagen Golf Consumption
Premium Support

Post08-05-2009, 21:09    Subject: TDI Catalytic Converter Replacement Quote

roorback wrote:
Now, I would like to know if and what benefits this actually brings?


It depends on what you mean.

Regarding performance: nothing.

Regarding the volume: a little louder.

Regarding the operating license: it expires icon_wink.gif.
MfG. Michael

VW Golf IV TDI GTI 4-Motion Bj.2002 MKB/GKB: ARL/FEK
VW T4 Pritsche TDI Bj.1999 MKB/GKB: AXG/AFK (Selfmade)


Translated on 04-10-2026, 6:07.
Back to top Profile PM Garage
roorback
Blaumann
Blaumann


Joined: 12/22/2003
Posts: 374
Karma: +1 / -2   Thank you, like it!
Location: kärnten/österreich

Free account, no CAN development support

Post08-05-2009, 21:14    Subject: TDI Catalytic Converter Replacement Quote

Thank you for the answer.

Not that I'm going to start messing around with "DIY tuning in muddy garages" – I certainly don't intend to do something like that, especially if it's pointless.
I was actually hoping for a solution to my question that explains something similar to the situation with the AGR (Abgasrückführung) system – which, while not improving performance, has problematic operational aspects but makes technical sense...

I've also heard about that, apparently a cat could get stained or something.

Okay, so why do people do things like that?

I once knew someone who modified his car's catalytic converter himself and claimed it gave him 10% more power with a 2.0-liter 16-valve gasoline engine, which might have been true. But what about with a TDI (diesel) engine?

Sure, here is the translation of the text from German to English:

"Hello"
volvo 850 tdi - 2.5l AEL aut. bj.96 - bald 500000km
volvo v70n 2.4 - 2.5l 5Zyl Sauger bj. 2005


Translated on 04-10-2026, 6:08.
Back to top Profile PM
TDI-GTI-4-Motion
Profi-Schrauber
Profi-Schrauber
Avatar-TDI-GTI-4-Motion

Joined: 02/22/2009
Posts: 3865
Karma: +127 / -0   Thank you, like it!

2002 Volkswagen Golf Consumption
Premium Support

Post08-05-2009, 22:49    Subject: TDI Catalytic Converter Replacement Quote

Das entfernen des Kats bringt nie was. Besides:

-The cat is simply too small for the engine (which is rare).
- The catalytic converter is either clogged or otherwise defective, causing insufficient exhaust flow.

If the latter is the case, it results in a "performance increase," although it's not really something that can be called an increase. It's more of a restoration of the original factory performance.


If you really want to know my honest opinion:

Get rid of that thing; it's just as much junk as the EGR. icon_wink.gif And if it's no longer there, it can't break down anymore. } It doesn't provide any performance, but at least it gives you a good conscience (of course, not from an environmental perspective). }
MfG. Michael

VW Golf IV TDI GTI 4-Motion Bj.2002 MKB/GKB: ARL/FEK
VW T4 Pritsche TDI Bj.1999 MKB/GKB: AXG/AFK (Selfmade)


Translated on 04-10-2026, 6:10.
Back to top Profile PM Garage
teileklaus
Schrauber
Schrauber
Avatar-teileklaus

Joined: 12/30/2006
Posts: 2643
Karma: +12 / -0   Thank you, like it!
Location: Obrigheim
2005 Volkswagen
Premium Support

Post08-05-2009, 23:13    Subject: TDI Catalytic Converter Replacement Quote

My opinion: removing parts only causes trouble, doesn't improve performance, and leads to modifications that need to be addressed during the next vehicle inspection.
Let them in!
I am providing only legally sound recommendations, to the best of my knowledge.
Opinions are divided regarding the DPF, and there may be some disadvantages associated with it.
Gruß, der Teileklaus
Touran 2017 DFG SCR 2,0, 150 PS Schalt
Fiat 500, Einkaufswagen
R1240R BIG Bore Tuningkuh, 142 NM


Translated on 04-10-2026, 6:11.
Back to top Profile PM Email Garage
TDI-GTI-4-Motion
Profi-Schrauber
Profi-Schrauber
Avatar-TDI-GTI-4-Motion

Joined: 02/22/2009
Posts: 3865
Karma: +127 / -0   Thank you, like it!

2002 Volkswagen Golf Consumption
Premium Support

Post08-05-2009, 23:34    Subject: TDI Catalytic Converter Replacement Quote

It seems like this is one of those topics where "you ask 10 people, and you get 10 different opinions." You've already heard two different perspectives. Now, it's time for you to form your own opinion. You've certainly received enough technical information.
MfG. Michael

VW Golf IV TDI GTI 4-Motion Bj.2002 MKB/GKB: ARL/FEK
VW T4 Pritsche TDI Bj.1999 MKB/GKB: AXG/AFK (Selfmade)


Translated on 04-10-2026, 6:12.
Back to top Profile PM Garage
Olaf



Joined: 04/16/2002
Posts: 307
Karma: +0 / -0   Thank you, like it!
Location: Bargteheide

Free account, no CAN development support

Post10-05-2009, 10:26    Subject: TDI Catalytic Converter Replacement Quote

If it's not causing any problems, leave it as it is.
The next time a retrofit DPF needs to be replaced, it will have to be replaced anyway.
If the TÜV inspector taps on the catalytic converter and it's defective, he'll hear it even if it's empty. It really just depends on whether the car as a whole attracts attention.
"I've been driving with a disconnected AGR hose for years and have always passed the technical inspection without any issues. This is because no one expects anything to be wrong with the car. They also have no interest in failing me, as the car is obviously well-maintained and doesn't have any cheap modifications. Even if the inspector notices the chip and extended gearbox during the test drive, they would never penalize me for it, because they can see that the car drives well in its current configuration."
I've found that people tend to pay closer attention when measures are technically nonsensical or overly conspicuous.


Translated on 04-10-2026, 6:13.
Back to top Profile PM Email
wolle
Blaumann
Blaumann


Joined: 05/23/2002
Posts: 176
Karma: +16 / -0   Thank you, like it!


Premium Support

Post14-05-2009, 14:52    Subject: TDI Catalytic Converter Replacement Quote

Hello,

Take a look here: /viewtopic.php?t=7048

This is a technical article.



Best regards,
Wool.
2018er A6 Avant Allroad, 3.0 Bi-TDI mit prima Ausstattung

96er A6 C4 Avant TDI, 2.5er AEL,6 Gang, Serienleistung, aktuell 615.000KM


Translated on 04-10-2026, 6:15.
Back to top Profile PM
roorback
Blaumann
Blaumann


Joined: 12/22/2003
Posts: 374
Karma: +1 / -2   Thank you, like it!
Location: kärnten/österreich

Free account, no CAN development support

Post14-05-2009, 14:54    Subject: TDI Catalytic Converter Replacement Quote

"Thank you."
volvo 850 tdi - 2.5l AEL aut. bj.96 - bald 500000km
volvo v70n 2.4 - 2.5l 5Zyl Sauger bj. 2005


Translated on 04-10-2026, 6:15.
Back to top Profile PM
New Topic Reply 🔗 ⭐ 🖨 Dieselschrauber - Index » Diesel Engine Technology
Similar articles and topics
Topic Forum
No new posts TDI Synchronization Angle: What is it? Faults & Documentation (Audi, VW, Seat/Cupra, Skoda)
No new posts Timing belt replacement on a 1.9L PD TDI Troubleshooting & Guides
No new posts WIV reset on VW Polo 9N TDI Faults & Documentation (Audi, VW, Seat/Cupra, Skoda)
No new posts Best LMM Diode Replacement: Optimal Choice Diesel Engine Technology
No new posts MSA12 replacement, what fits? Diesel Engine Technology
No new posts Golf 4 TDI: Strange Noise When Engine Stops Diesel Engine Technology
No new posts Is an internet connection mandatory when accessing ECUs? On-Board Diagnostics (OBD)
Jump to:  
You cannot post new topics in this forum.