KAT approval for AU

Hello everyone.

I'm now faced with the question of whether to keep the catalytic converter in place during my engine conversion or not.

I'm actually worried that I might run into problems with my next sick leave.

During the last inspection, my engine had to be revved up five times before the readings were correct, because I had been driving a lot in the city.

Does anyone know how that works?
Is the KAT crucial for the AU?

Best regards,
Olli

Hi,

The cat is crucial for the ABE! Therefore, please leave it in.

Best regards,

Jan.

Hello everyone.

I'm now facing the question of whether to keep the catalytic converter in place or remove it during my engine conversion.

I'm actually worried that I might run into problems with my next sick leave.

During the last inspection, my engine had to be revved up five times before the readings were correct, because I had been driving mostly in the city.

Does anyone know how that works?
Is the KAT crucial for the AU?

Best regards, Olli

Hello,
Fresh engine oil before the next inspection, and then 100 km of full throttle on the highway!
Best regards,
Günther.

In addition, the AU also includes a visual inspection of the exhaust system. And the fact that the catalytic converter is missing should be noticeable.

Hi.
I took a look at your planned renovation.
How are you going to proceed now ? Do you have an emissions test report for the larger turbo ?
If you're modifying your exhaust system to be larger than the stock size, I recommend a sports catalytic converter (around €500, made of stainless steel). The advantages are: it helps comply with Euro 2 regulations if your engine has a turbocharger or similar modifications; it allows for more gas flow, which *may* result in more torque than the stock catalytic converter (although this may not always be noticeable and depends on the overall tuning modifications); and, crucially, the catalytic converter can be registered for use.

Best regards,

So, the sick leave is approved, even without a doctor's note!
The proportion of soot will not be significantly higher in this case.
The HCs (likely referring to a specific measurement) only increase slightly, which isn't a significant factor in the overall result.

However, during a properly conducted exhaust emissions test, the inspector will notice during the visual inspection that there is no...
If a cat is present, then

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

'MFG' is an abbreviation for 'mit freundlichen Grüßen,' which means 'best regards' or 'sincerely.' It is commonly used in German-language emails and letters.

Why?
If you just rinse it out, then it doesn't really matter.

He didn't say that he wants to replace him with someone else .

"The components inside are just unnecessary and uselessly increase the exhaust backpressure."
which also reduces its efficiency.

Of course, mine is still in .

It persists even if the engine is otherwise in good condition. Previously, I manipulated the mass airflow sensor (MAF) signal so that the engine runs with an excess of air.

Two diodes are placed in the LMM (mass airflow sensor) signal line, and the fuel injection amount is adjusted relative to the airflow, which reduces power, but the exhaust emissions are 'at the level of a new vehicle.'

Hello everyone!
I drive a 1997 Volkswagen Passat 3B TDI with a 1.9L engine and 90 horsepower.
The engine control unit has switched to emergency mode because the catalytic converter is clogged (according to the workshop's diagnostic tester), which is causing excessive back pressure. Would it be beneficial to remove the catalytic converter and clean it with a pressure washer, spraying it in the opposite direction of the exhaust flow?
Is that a good idea?
Will he sit down again afterwards (perhaps even sooner)?
What else, besides exchanging, could lead to a solution?
Can you get a sick leave certificate with a cat sitting on you?
That's what I have planned for this month.
I have also considered Steffarn's 'mechanical' cleaning method using a screwdriver.

Is it even common for a Kat to sit down? With 237,000 km, my first engine literally flew off .
I've been driving the replacement car (which had 40,000 km on the clock) for a few months now, so the Passat has now reached a total mileage of 245,000 km.


Thank you for any suggestions you may have.
André S.

Hello,
I've heard reports of clogged catalytic converters before, but I've never actually seen one. In gasoline engines, it's usually something with the fuel injection system or the engine control unit. Even after a workshop diagnosis indicating a clogged catalytic converter, the vehicle often runs normally once the underlying issue is fixed. Of course, catalytic converters are quite expensive, so it's a shame when they're wrongly diagnosed.
I would try disassembling the catalytic converter and see if there are any visible issues, especially if no other problems can be found. If in doubt, you could try blowing it out with compressed air.
Does your car emit so much smoke that it creates an impenetrable wall of fog behind you?
Good luck, Benno.

Is it even common for a cat to sit down?

more likely to be less, except in the extreme short-range area.

Most of the time, the catalytic converter breaks down and either blocks the exhaust flow or crumbles and then clogs the muffler.

The former occurs more frequently...

CU Gremlin.

Hello Gremlin,
Thank you for the tip.
Since I drive long distances (over 100 km daily to work), that probably won't be suitable for me.
But I'm going to take a closer look at the cat and examine the monolith. Can you tell if it's crumbling?
If not, I can remove the cat, close the gap in the exhaust pipe, and then test to see if the back pressure is still too high, because the muffler might be blocked.

Thank you for the suggestions!!!

Best regards,
André.

Hello Benno,
I already have a well-founded trust in the workshop. Firstly, it is not a VAG workshop, and secondly, my brother works there as a body builder.
I'll also try using compressed air.
I don't really produce excessive amounts of black smoke, at least no more than other TDIs.

Okay, here's the translation:

Thank you.
André S.

Hi,

'I've also had a twisted monolith before. On the way to southern France, exiting the Brenner Pass with a trailer attached, I managed to reach the next parking area at 30 km/h. With the help of various tools and information from other truck drivers, I removed the catalytic converter, crushed the ceramic material inside, reinstalled the empty catalytic converter, and continued on my way. It took about 4 hours due to the poor tools and the lack of a proper mounting pit.'

However, before that, he could be heard making a distinct clacking sound.

Hello,
'I 'mechanically' cleaned my cat's urethra on Saturday. While it appeared to be okay at least visually on the entrance side (I couldn't see the exit due to the curvature), I cautiously inserted an iron rod just to be sure.'
After the error memory was reset, the error did not reappear.
I'm now curious to see the results of the AU (presumably a medical test or analysis). I was planning to have it done next week.
Best regards,
André.