STG Recalibration: What Happens Inside?

Hello everyone,

What exactly happens inside the control unit when it is reprogrammed (e.g., to 00011)?

I suspect that a different mapping is being used.

However, why is an error produced when converting, for example, from 00002 to 00011 (replacement control unit)? Would it be possible to suppress this error?

See you then... Best regards, Gunnar.

t3_tdi wrote:

I suspect that a correspondingly different characteristic curve is used.

This assumption is, in my opinion, "much too one-dimensional" .

It is possible that the expected communication within the CAN bus occurs without accessing other (performance-relevant) data fields (as apparently happens with the 9N TDI).
So, overall, it's about integrating into the vehicle-specific environment of the respective ECU (Electronic Control Unit).

'With coding, you're telling the control unit with whom it should communicate. In the case of engine control units, for example, if it was originally coded for German vehicles and then recoded for the US market, the speedometer might display miles instead of kilometers. The engine control unit doesn't use a completely different map; it only stores one map within its memory, which is equipped with a RAM. This makes it adaptive, meaning it can learn and adjust.'
This is often also the case with automatic control units.

Best regards,

Thomas Falke.

It only has one Kenfeld file stored in it.

I'm not familiar with that. As far as my information goes, each control unit contains multiple parameter maps, each of which controls different parts of the system.

For example, in TDI engines, there are characteristic curves (maps) for parameters like boost pressure, pump voltage, and injection timing, and these all form a data set.

Multiple datasets can also be contained within a single control unit, which can then be activated, for example, through a coding scheme (or other parameters).

If I'm wrong, please feel free to correct me.

I watched a tuner create a dataset. It was just one dataset with a single lookup table (or map) that contained multiple parameters, such as EGR, boost pressure, load, and speed limiter, all within that one table.

Best regards,

Thomas Falke.

Hmm...

I actually meant the following re-coding.

00001 (Automatic)
00002 (Switch)

00011 (Replacement Control Unit)

When installing an AFN engine into a T3 vehicle, warm-start problems can occur with certain engine control units (ECUs). By reprogramming the ECU, for example, from code 00002 to 00011, the vehicle will start perfectly every time. However, this will create an error (which is also indicated by the flashing pre-glow LED) in the error memory.

The engine control unit (ECU) seems to be injecting fuel differently after the reprogramming, especially when the car is warm. I therefore suspected that there might be a kind of generic map that always works.

But why is an error being generated in the error memory now?

greetings Gunnar[/quote]

I watched a tuner create a dataset, and it was just one dataset with a single table where multiple things were contained, such as EGR / boost pressure / load / speed limiter, etc... as I said, everything in one table.

Best regards,

Thomas Falke

There are definitely several characteristic fields (cold/warm/hot) on your chip. As far as I understand, the tuners only adjust the characteristic field for an engine that is at operating temperature. Therefore, your observation is correct -> but there probably are more characteristic fields if you look around in the http://www.chiptuningforum.com.

Why do problems only arise after the renovation?

Then, something definitely wasn't fully taken over, but that has nothing to do with the coding anymore.

If I break my arm, it hurts. If I then shoot myself, nothing else will hurt, but the fracture is still not healed.

m;

In the engine control unit, no other map is used; only one map is stored within it, and this map is equipped with a RAM memory, making it adaptive, which means it is self-learning.
This is often also the case with automatic control units.


Be careful!

The Motronic ME(D)-x has static RAM for learning values.
EDC does NOT have static RAM for learning values (this will be implemented in the future).

The EDC (Electronic Control Unit) in VAG vehicles has two basic configurations (manual/automatic transmission) that are switched using coding. Additionally, coding can also be used to define communication with other control units or equipment features, which is completely customer-specific.
All dynamic changes within the system are calculated in real-time (e.g., quantity adjustments, injection start timing during warm-up, etc.).
Since the diesel engine (currently) doesn't operate with a lambda control loop, a continuous adaptation process is not necessary. In gasoline engines, this is essential; otherwise, there would be terrible jolting during every engine start.

By the way, there are a lot of identification codes in the EDC. Tuners probably don't even know half of them.


CU Gremlin.

Hello Gremlin, do you have a program that can make the key fields visible, and even show the meaning of the individual bits?

A program for visualizing and modifying characteristic maps, such as WinOLS, is available. It also comes as a demo version, but then without the ability to save data.

The meaning of the bits will not be given to you easily . Instead, enormous sums of money are offered for them. However, you can find some important identifiers and their meanings, for example, in the chip tuning forum. (As always: searching is also helpful there...)

Regards,
Guste.

Why do problems only arise after the renovation?

Unfortunately, I cannot answer that. If only I knew...

Then, something definitely wasn't fully taken over, but that has nothing to do with the coding anymore.

'So, there are no error codes stored, and all the sensors have been checked. Some people suspect that it might be related to the tilted engine mounting position in the T3.'

'Interestingly, this phenomenon only occurs with certain control units. Previously, I had a control unit from a Golf 3 (year 1997) installed, which was then replaced by a control unit from an Audi. Now, it starts perfectly in any temperature.'

Since replacing the control unit (STG) is usually quite expensive, I didn't think the idea of reprogramming it was so bad, as I know several owners of electric motorcycles who have a similar problem.

Perhaps the problem can be solved by adapting certain values within the engine control unit (ECU). I would be very grateful if anyone has any ideas on this.

best regards, Gunnar