Speeding Ticket: 195 km/h!

Hello fellow diesel enthusiasts,

'Since yesterday, I've been experiencing a 'power loss' starting at 195 km/h (according to the speedometer). It's like someone is pressing the brakes. The maximum speed isn't always reached.'
I previously examined the mass airflow sensor (MAF) and cleaned it with brake cleaner. The internal housing and ceramic plates had a slight black coating. Since cleaning, it seems to be drawing air better again.
Air filter is new... all charger pipe hose clamps have been replaced with reinforced ones (wider stainless steel clamps).

Oh, so... my AGR valve is clogged .
I'm going to get the AGR system working again... I'll clear the blockage in the pipe... let's see what happens then.

Hmm... and I think there's still something 'blowing' out of the engine compartment... starting around 2300 RPM... but I can't find any leaks on the hoses.

It's possible that the problem is related to the solenoid valve in the middle of the charge air pipe... there's a fine oil mist around the connector that sticks out of the pipe, and it seems to be occasionally making its way to the rear of the engine.

A4 - AFN - 107,000 km

Unfortunately, there are many symptoms.


Regards,
Carsten.

A4Carsten wrote:

Since yesterday, I've had a "power loss" starting at 195 km/h (according to the speedometer}...it's like someone is pressing the brakes. The maximum speed is not always reached..... Oh, so... my AGR valve is clogged . I will try to make the AGR system work again. I will remove any blockage in the pipe. Let's see what happens then.

Hi.

The action involving the AGR (Abgasrückführung system) probably won't achieve anything, because it's already closed under full load. It could even get worse if the valve doesn't close properly.

Quote:

mhhh.....and I think there's still something "blowing" in the engine compartment...starting around 2300 RPM...but I can't find any leaks on the hoses. It's possible that it has something to do with the solenoid valve in the middle of the intake pipe... there's a fine oil mist on the connector that sticks out of the pipe, and it seems to be getting into the rear of the engine (probably occasionally

).

"And the rest of the sentence?"

What you might be mistaking for a solenoid valve in the middle of the intake pipe is likely the charge air temperature sensor. If air is leaking from there under load, it can certainly cause a loss of power. In cases of larger air leaks, it can even lead to excessive soot emissions.

Hello Ulf,
Thanks for the tip.

Think about the possibility that the LMM is creating the hole.

'When I'm driving in 3rd or 4th gear, for example, at full throttle... above 4000 RPM, the car runs perfectly. But now, in 5th gear, the fuel injection starts to adjust and become too lean, starting at around 185 km/h (due to high air pressure in the air filter housing). I'll probably buy a new mass airflow sensor (MAF) on eBay; it's probably due for replacement anyway.'

Unfortunately, I no longer trust any workshops in this area... even though VW-Stadt Kassel-Baunatal .

It's a shame that the TDI engines have so many side effects ... the days of the virtually indestructible Daimler long-stroke engines are over... even though they might have used a few more liters of diesel fuel .

I need to see if I should buy a VAG-COM.
mhhh..so, it's a real hobby...the TDI..although I'm already struggling } with the motorcycle.

Greetings to all diesel mechanics.
Carsten.

Hi,

As mentioned before, I no longer trust any car repair shop... except for tire changes (although I also do that myself ).
Probably a consequence of our hectic society, that the young people can't do or leave anything in peace anymore... (The boss only sees numbers ).

I removed the splash guard from my A4... and there it was: a longitudinal crack in the charge air hose, which is connected to the VTG... I temporarily (until tomorrow) taped it up with thick electrical tape... the MAF sensor had already been cleaned... now the `OLD` one is working again... like a champ .

`ULF-Test`... Air temperature: 20 degrees Celsius. 2000-4000 RPM. 6.8 seconds... 1315 kg with me (90 kg). Original tires on aluminum rims, 30 liters of diesel on board... 110 HP AFN engine (without modifications)... I think that's pretty good.

Yesterday, I added 400ml of Diesel-Fit (ATU) to the fuel tank (a cleaning agent for the entire fuel system).

Vintage push rod, treated with copper paste (from the neighbor).

Tomorrow, additional V2A stainless steel hose clamps will be installed on all the remaining lower loader pipes.

Then I hope everything will be quiet. By the way, after the brake cleaner bath, I also sprayed the mass airflow sensor with isopropyl alcohol (a residue-free cleaner).

The speedometer now goes up to 220 again (which is rare).


Now I'm just annoyed about my own home workshop... I specifically said that everything should be checked... well... I was too lazy to remove the splash guard... but they're charging me a lot for other parts.
I don't want to dwell on what could have happened (a persistent drop in charging pressure on the VTG).


And finally, I think to myself... what's the point of the internet (with all its knowledgeable people) ...
Thank you for the general tips that are available in this forum!

A4 AFN, year of manufacture 1996.

Best regards,
Carsten

Wow... 220 km/h on the speedometer... My car maxes out at around 207 km/h, and that's only going downhill. It's a Golf III, probably weighing around 1200 kg, and also with an AFN engine.

Okay, I have slightly larger tires on... maybe that's the problem.

Best regards.