G3 AFN, Following the 2nd. Start: Lack of power

Hello everyone in the forum community,
I just used the search function, but nothing really seems to fit. Perhaps someone is familiar with this effect.
I leave for work at 6 a.m. every morning, and everything is fine. After driving for a few kilometers, I stop at a bakery (or gas station, etc.), continue driving, and the turbocharger pressure doesn't reach the usual level, it's about 0.8 bar lower.
If I then turn off the engine, let it roll for about 50 meters with the ignition on, and restart it, everything works normally again.
It's not dependent on the time of day , I just came from work, everything is OK, I just unloaded some empty bottles at home, I'm going to the beverage store, and the charging pressure is low again. Turn off, roll up, start, that's good.
There's nothing in the error memory. I only know that letting the engine idle doesn't work when the ignition is off.
Okay, humans tend to adapt to (almost) everything, but if you have any suggestions, I'm grateful for any advice.

What are we actually talking about? Tanks, motorcycles, trucks, toy cars? A few data points would be helpful.

Sorry, but my car's details are listed below in my signature, and the title says G3 AFN...
But I have another update: I don't need to let it idle; it's also enough to just let it sit for about half a minute with the ignition on. And it doesn't matter how long I've been driving beforehand.

Are you absolutely sure there are no error codes stored? It's practically impossible to have a problem with the turbocharger pressure regulation without any error codes. How did you measure the turbocharger pressure? Via an external display, or using VAG-COM in the control unit?

The error memory is as empty as my bank account at the end of the month. Honestly!
I installed a small, fun mechanical pressure gauge that reads from 0 to 1.6 bar, but VAG-COM shows me roughly the same difference, but different values. I think it's because the control unit measures the absolute pressure, while the pressure gauge measures the relative pressure.
Normally, my pressure gauge goes up to about 1.2 bar when accelerating, but in case of a fault, it fails at around 0.4 to 0.6 bar.
I'm unable to post the log file right now because I'm still at work.
Here are a few more details, in case they are relevant: This is not a fail-safe mechanism, and I am familiar with the effect.
The LMM (lambda measuring module) has been replaced with a diode 2.5 years ago, and the EGR (exhaust gas recirculation) system has been neutralized.

How many kilometers does your car have on the odometer?

Hi Snowman, were you able to resolve your issue? It seems like I'm experiencing the same problem, and I urgently need a solution. Okay, let me describe how it looks like for me again:


1. Golf III TDI GTI (AFN) (www.golf.frenke.de) Mileage: 311,000 (!!!) However, the digital odometer displays only 11,000. It jumped from 299,999 to 0 *LOL*

2. In the morning, start the engine (when it's cold), warm it up on the track, and then, once it's warm, accelerate. Achieve full power without excessive smoke or blackening. Everything's fine!

3. After work, (engine cold), started driving normally, full power, no black smoke.

4. Refueling/Shopping: The engine is warm, turn it off, and after refueling/shopping, start the engine and let it warm up.

5. On the track: Now, after the initial start, there's significantly less power (around 60 horsepower), and when I floor it, there's a huge cloud of black smoke behind me. If I give it a little less gas, it might have around 65 horsepower and doesn't smoke anymore. (I haven't tried turning it off and leaving the ignition on yet!) (I'll probably do it tomorrow!)

6. Occasionally, when I drive with full throttle for a longer period (approximately 5-10 minutes), the engine goes into a limp mode. Then, I only have 20 horsepower , and I have to turn off the engine, restart it, and then it goes back to normal (with 65 horsepower). However, that has only happened maybe 10 times in the last 3 years!



Since my VW dealer isn't very knowledgeable, I wanted to get your opinions first!


I hope you can help me!


Questions?

Best regards, Christian.

The engine control unit's (ECU) fault memory in your Golf probably hasn't stored anything.

"Notprogramm" = Error memory entry, unless the software in the control unit is corrupted.

Okay, so when I read the data from the engine's control unit, it displays the following:

65535 - Internal Control Module Memory Error.
37 - 10 - Faulty - Intermittent


I actually tried it today: When I turn off the engine and then briefly start it again with the ignition on, it DOESN'T do anything! Too bad, it would have helped me a lot!

What do you think about that?

Okay, error codes are helpful, but can't you already tell what the problem might be based on (the detailed) description?

It's quite strange that it only happens when you briefly turn off the engine and then turn it back on, and never at any other time!

krischi83 wrote:

So, when I read the data from the sensor block connected to the engine, it outputs the following: 65535 - Internal Control Module Memory Error. 37 - 10 - Faulty - Intermittent I actually tried it today: When I turn off the engine and then briefly start it again with the ignition on, it DOESN'T do anything! Too bad, it would have helped me a lot! What do you think about that?

Bad.

Possible causes and effects of this:
- Control unit defect, emergency program activated, but sometimes with no noticeable effects depending on the exact location of the fault.
- Control unit not defective, but the data set is incorrect (bad tuning), emergency program may or may not be active, depending on the data set.

Best regards, Rainer.

hi, ok...

Let's put the emergency program aside... I think that's a different error, and I'm not too concerned about it because it happens so frequently.

What's more important to me is the question of why I experience less power and more black smoke during a warm start... Surely, the engine control unit isn't getting "too hot," is it?


It seems that leaving the ignition on for a while and then restarting the car actually works. After that, I was back to my normal performance...

The lack of performance is due to a bug.
The emergency program is a safety feature designed to prevent further damage (including environmental damage, for example, if it produces excessive soot) and to force the user to take action.
After restarting, the emergency program is initially reset. It keeps happening again because the error is still present.
Okay, so the process is to read the error codes, delete them, and then read them again. Then post it here, and we can continue with troubleshooting.

The engine doesn't go into emergency mode... or rather, it only does about 10 times in the last 3 years. I don't care at all! That's so rare, it doesn't bother me at all!

I'm experiencing some performance degradation during a warm start. According to your theory, the error should disappear with each start and then reappear. However, that's not what's happening. He only starts on the second attempt or after a warm start.

Hey Kirschi!

krischi83 wrote:

The engine doesn't go into emergency mode... or rather, it only does about 10 times in the last 3 years. I don't care at all! That's so rare, it doesn't bother me at all! I'm experiencing some performance degradation during a warm start. According to your theory, the error should disappear with each start and then reappear. However, that's not what's happening. He only starts on the second attempt or warm start...

What don't you understand or can't understand about KlausiMausi's advice? *with-pink-cotton-swab-throw*

"Doctor, my little toe hurts!" Especially if I... but I don't care, because I've only done it 10 times in the last 3 years...
"What else can I do after my exam without having to show you my... well, you know?"

My answer: Wait until it falls off .

Got it?

Best regards from Munich!