AFN/Russ Issues: Troubleshooting Performance Problems

Hello everyone,
A few weeks ago, I had a hole in a vacuum hose, which meant it wasn't producing any power.
Okay, here's something new:
1.9TDI (AFN) ca 245000km. Manufactured in 1996.

"There's quite a lot of soot coming out of the exhaust, both on the highway and in city traffic; it smokes heavily, black smoke, and the car gets dirty very quickly at the back. (However, it only produces soot for a relatively short time, not constantly)."
Partial power loss (very brief). This morning, it wasn't reaching its maximum speed; instead of the usual 190-195 km/h, it was only going 180 km/h.
As far as I can tell, everything seems to be sealed correctly with the hoses. The boost pressure was lower last night in the garage, a maximum of 1400 instead of 1900. After restarting, it's back to 1865-1900. Yesterday evening, the error code displayed was 575 17-00.

New turbocharger control solenoid valve, new air filter and diesel filter. Sufficient vacuum pressure is present. Could the EGR valve be the problem (pressure is also reaching the valve and the associated component)?

Is my turbo going to cross the river? (Please no!!)

Thank you for your suggestions!

'Please cover the EGR valve with a metal plate.'

Are you from Wiener Neustadt? (Your username kind of gives it away...)

Hey, no, but I'm often in Wiener Neustadt (I fly for Diamond Germany).
I probably have two left hands when it comes to fixing things.
Is it enough to simply disconnect the connector from the EGR valve at the solenoid valve?

Hello,
I think I've found the problem: there's a hole in the hose clamp at the bottom of the LL pipe where it connects to the bridge, and that's where the air is escaping.
Is that then the explanation for the low turbo boost (Russ) and the low maximum speed (Vmax), especially when the exhaust gas recirculation (AGR) system is active? Don't laugh, I'm just learning about this stuff!

Yes, that's the explanation. The turbocharger also mixes exhaust gases with the air it forces into the engine, and it injects more air than can be supplied as fresh air to the cylinders, which is why there's soot.

The boost pressure isn't being achieved because it's leaking out. It's like trying to inflate a tire that has a hole in it. You can pump and pump, but the tire won't reach the desired pressure.

I think I've found the problem; there's a hole in the LL pipe, specifically at the bottom of the hose clamp that connects to the bridge, and air is escaping from there.


Congratulations - it's great that you were able to find the error so quickly .

Hey, no, but I'm often in Wr. Neustadt (I fly for Diamond Germany).


Okay, otherwise you could have packed your drone into the airplane, and I could look at it next time I come to Neustadt.

Yes, that would be the explanation. The turbocharger also mixes air with the exhaust it expels and injects more than what is available as fresh air into the cylinders, hence the soot.

The boost pressure is not being reached because it's venting.

Yes, that's correct – it should be mentioned that eventually, the emergency mode will activate and an error message like 'Intake manifold pressure control difference' will appear if too much air is lost.

A faulty turbocharger could also be the cause if you push an engine with a leaking low-pressure (LP) turbine too hard.

Okay,
Thank you for your feedback.
"I think an auxiliary fuel tank (AFN) would barely fit in the DA40, but probably not without modifications."

Otherwise: Today I bought a piece of hose about 10 cm long from the local hardware store for €20 and installed it – and there you go, it's working again.
Question: I disconnected the EGR connector; I read that it's supposedly better. What does it do, and more importantly, is it enough to just reconnect it before the emissions test (in 2 years)?

Best regards.
Julian.

Question: I disconnected the AGR connector; I read that it might be better this way?

Don't disconnect the electrical connector – that will create an error code. Instead, you need to detach and seal the thin vacuum hose connected to the EGR valve.



What's the point, and more importantly, is it enough to simply reapply it before the next inspection (in 2 years)?


Since I'm too lazy to explain that again -> https://community.dieselschrauber.org/en/viewtopic.php?t=3095

No, there are no problems with the official inspection (AU), unless the inspector notices sloppy workmanship that suggests something is wrong.