Larger Intercooler Installation: Guide & Benefits

Hello everyone!

I have a question or concern.

I installed a larger intercooler (+ stainless steel pipes, etc.) in my Golf 3 TDI. Unfortunately (due to my own carelessness), I didn't pay attention to a test report or ABE (General Operating Permit) when I bought the intercooler! So, I now have an intercooler without an ABE, and as a result, the 'dear' TÜV (technical inspection authority) refuses to register it.
Now, my question to you. Have you had similar experiences before, or do you perhaps know where one can obtain such comparative expert opinions?
I would be very happy to receive many responses!

Best regards,

Hi.

Have you already been to a TÜV inspector (and did they say no)?

We took our T3, which has been converted to run on vegetable oil, for the TüV inspection (just for the regular technical and emissions tests), and the inspector was curious about all the piping.
After I explained something to him, he said "Oh, cool" and then proceeded with the usual examinations.

If you haven't changed anything else, a larger LLK (likely referring to a Large Language Model configuration) will probably consume more resources than it provides, so nothing needs to be entered there, I think.

When looking for a suitable inspector, you're more likely to find someone knowledgeable than to find an ABE (General Operating Permit), especially if you don't even mention the manufacturer of the lighting system.

m;

Yes, that's how it is. I was already with an inspector, and he said it. Without a test report or ABE, nothing will happen .

Goto other Prüfer

Okay, I'm also not aware of any way to get a low-voltage lighting kit (LLK) registered at an affordable price. If anyone knows a solution, please post it! Are there LLKs available with an ABE (General Operating Permit) or a test report?

Weld the pipes, paint them black, add a few VW and Audi emblems (perhaps create custom stamps), make sure everything looks original, and don't worry about getting it registered.

Our G3 with the AAZ engine also has an aftermarket intercooler (it didn't have one originally), and we've never had any problems with it. With your TÜV inspection in Germany, I'm starting to get the impression that it's being overly strict if you show up with even a speck of dust on your windshield for the inspection .

Hello.

Attach pipes, paint them black, add a few VW and Audi emblems (possibly create stamps), make sure everything looks original, and don't worry about the registration...

Our G3 with the AAZ engine also has an aftermarket intercooler (originally it didn't), and we've never had any problems with it. With your TÜV inspections in Germany, I'm starting to get the impression that they're being difficult if you show up for an inspection with even a speck of dust on the windshield .

'In my G3 with the AAZ engine, I simply installed the glow plug relay from a G3 TDI.'
'I simply replaced the curved adapter for the intercooler hose on the intake manifold with the one from a Passat 35i with a supercharged engine. The hose from the intercooler then fit perfectly and runs just a bit tight behind the oil separator on the valve cover.'
I then simply mounted the original hose between the charger and the intake manifold, attaching the intake manifold side to the charger.
As an adapter between the two pipes, I cut a piece of pipe (from the scrap pile of a pipe bending company) to the right size, installed it, and didn't even bother to paint it.

So, then I went to the TÜV for the vehicle inspection (Hauptuntersuchung). The load carrier system (LLK) wasn't a problem, and after the inspection, it's essentially as registered. In any case, there shouldn't be any serious issues with it, whether it's used or not.


Best regards,
huebi

...
So, then I went to the TÜV for the vehicle inspection (Hauptuntersuchung). The load carrier system (LLK) wasn't a problem, and after the inspection, it's essentially as registered. In any case, there shouldn't be any serious issues with it, whether it's used or not.



I seriously doubt that. If you cause an accident, which may be due to excessive speed, and the vehicle is then thoroughly inspected, there's likely to be trouble.

Hati wrote:

I seriously doubt that. If you cause an accident, which may be due to excessive speed, and the vehicle is then seriously inspected, there will likely be problems.

Okay... for example, a (well-hidden) 10cc tuning or larger injectors will also not be considered legal if the inspector overlooks them during the vehicle inspection (TÜV).

@huebi:
Even if you try to come up with an excuse, the predictable and aggressive response would be, "Then prove that it wasn't installed after the technical inspection!"
And what do you do then?

I seriously doubt that. If you cause an accident, which may be due to excessive speed, and the vehicle is then seriously inspected, there will likely be problems.
Okay... for example, a (well-hidden) 10cc tuning or larger injectors will also not be legal if the inspector overlooks them during the vehicle inspection (TÜV).

@huebi:
Even if you try to come up with an excuse, the predictable and aggressive response would be, 'Then prove that it wasn't installed after the technical inspection!'
And what do you do then?

For evidence preservation, the following solution is quite practical:
Before taking the vehicle to the TÜV (German technical inspection agency) for inspection, take photos with at least two witnesses. Along with a sworn statement from the witnesses, send these photos via registered mail with return receipt to yourself immediately after the inspection. Have the witnesses accompany you to the TÜV so that the changes, as described, can be verified by the TÜV inspector.
The registered letter can then be opened by the judge if necessary, and it carries considerable evidential weight. In any case, witnesses who claim otherwise would have to provide very strong arguments to contradict it.
A practical application of this solution is for software that needs to be protected before patenting or to prevent competitors from exploiting it.
Although the process is quite cumbersome and also very intricate, it can prevent a lot of trouble.
The change in design only becomes interesting when it's the direct cause of an accident. For example, having a ridiculous 400 horsepower in a Golf isn't a problem at all if an accident happens in a 30 km/h zone at a speed of 30 km/h. A standard Golf would also reach that speed, so the 400 horsepower doesn't play a role in that scenario.


Best regards,
huebi

Well, after that, even in a 90 horsepower Golf, accidents at speeds up to 200 km/h are not a problem .

While the thread is a bit old, I still want to add my two cents.

In my opinion, it shouldn't be a problem to register a different LLK (likely referring to a catalytic converter), because according to the VdTÜV guidelines, modifications that increase performance by up to 5% and do not affect the ignition or fuel mixture do not require an emissions test or similar documentation. I highly doubt that a modified LLK would actually increase performance by 5%...

Forenheini wrote:

...and does not interfere with ignition and/or fuel mixture preparation... no emissions test or equivalent.

And that's likely where the problem lies: If colder, and therefore denser, air doesn't affect the fuel-air mixture, then I don't know what does...

guste100 wrote:

If cooler, and therefore denser, air doesn't interfere with the mixture preparation, then I don't know what does....

Okay, but...

An LLK (Low-Temperature Coolant) system is not a regulated system, but rather releases fresh air at a temperature that depends on factors such as the intake pressure, outside temperature, vehicle speed, and wind conditions (headwind or tailwind).
That means the LLK (likely referring to a specific device or system) is like a lottery generator for the actual fresh air temperature.

If I use a small, series-mounted intercooler (SMIC) at full throttle, the intake air temperature (IAT) is initially as low as with a large front-mounted intercooler (FMIC), almost like the ambient temperature. However, it then rises more quickly and to a higher level.

A larger LLK (Low-Temperature Cooler) essentially simulates lower ambient temperatures at high charging pressures compared to a smaller LLK, thereby reducing (under the current conditions) the LLT variations between partial load and maximum power.
With these smaller fluctuations in one of the "input parameters" for the exhaust values, I would expect to see better results rather than worse.

In the EU emission cycle, only low engine loads are used (for a 1.9 TDI engine that has to move between 1 and 1.5 tons), so the difference in cooling capacity (LLC) between a standard SMIC and a large FMIC is likely to be almost zero. This means that the official emission values would not be significantly changed or altered by a large LLC.