AGR Blockage: Causes and Solutions

Translated on 10-09-2026, 5:53.

Hello, today I removed my AGR valve to see if my intake manifold is also full of oil sludge! (Passat 98 - AFN - 135,000 km) But what did I find:

More pictures:
http://www.insel-MS.de/passat/agr2.jpg
http://www.insel-MS.de/passat/agr3.jpg
http://www.insel-MS.de/passat/agr4.jpg

At first, I thought someone might have already "tampered" with it, but it's definitely NOT sealed with metal.

How could something like that happen?

(I've left it like this for now, so I'll be the only one with a "real" defective AGR!

)

By the way, the intake manifold is verschandeln except for a thin film of residue! So, it must have been sitting there for quite some time.

Translated on 10-09-2026, 5:54.

Hi Ralf,

I'm assuming that the added end is the exhaust side.

Can you analyze the "Propf" in terms of its components?
Is that just soot (but it looks too compact for that), or something else / something that has been transformed?

Overall, it's quite a remarkable picture

.

Translated on 10-09-2026, 5:55.

Hello Ulf, of course, the "Propf" refers to the exhaust side.

It looks and feels like coal! That's why I suspect it's Russian.

It's quite hard, and you can see the break point clearly. (I had to use gentle force to break the valve off the exhaust pipe!)