A4 B6 2.5 TDI, Engine 180 hp, running unevenly

Translated on 03-07-2026, 15:19.

Hello everyone,

The car had been sitting in the yard for 1/4 of a year due to an accident. I've now started the repair work. The front section needed to be completely replaced, including the strut and cooler. During the disassembly, I noticed that the "indicators" on the tension pulley of the pump's Z-shaped belt were not aligned. I have now successfully disassembled and reassembled the mainspring housing, including the escapement mechanism, using a six-millimeter wrench.
Now I have started the car, and it is running rather roughly, and it is also smoking a bit when I give it gas.
After I unraveled the spring, it relaxed, and the hands moved far apart, and the strap was quite loose, but I can hardly imagine that it has jumped over. Now the strap is actually properly tightened.
Then I wanted to check the injection timing and found that the camshaft was probably defective (short circuit to positive, the injection timing is therefore not displayed -_-).
I have disconnected the actuator, but there is no change. Could it also be the actuator itself? I have driven with disconnected actuators before, and they worked perfectly normally. As for the 2.5L engine, it's probably not that important whether it's clamped or not...

01-05-2020, 12:08 Subject: A4 B6 2.5 TDI, Engine 180 hp, running unevenly

[Translating...]

mal angenommen der Riemen sei übergesprungen, dann wäre der Einspritzbeginn doch so extrem verstellt, dass er garnicht mehr anspringen würde, oder?

01-05-2020, 17:03 Subject: A4 B6 2.5 TDI, Engine 180 hp, running unevenly

[Translating...]

Moin,
das Einspritzsystem des BAU Motors funktioniert nur mit Signal des Nadelhubgebers.
Egal ob Kurzschluß nach Plus oder nicht angeschlossen, der Motor läuft im Notlauf.
hg
Herbert

Last edited on 01-05-2020, 18:12, edited 1 time in total.

[Translating...]

Ach ich doof, ist ein BDH. Wie geschrieben lief der ohne Probleme mit abgesteckten Hubgeber.

Last edited on 01-05-2020, 21:48, edited 1 time in total.

[Translating...]

Die Einspritzung des BDH funktioniert wie beim BAU.
hg
Herbert

02-05-2020, 16:26 Subject: A4 B6 2.5 TDI, Engine 180 hp, running unevenly

[Translating...]

Wann lief der Motor das letzte Mal rund?

Lässt sich lokalisieren welcher Zylinder nicht mit läuft?

03-05-2020, 20:59 Subject: A4 B6 2.5 TDI, Engine 180 hp, running unevenly

[Translating...]

Das war vor dem Unfall. Ich war jetzt heute nochmal dran. hab ihn 20 Minuten laufen lassen, danach war es besser. Mal schauen wie er läuft wenn er wieder fahrbereit ist.

05-05-2020, 19:19 Subject: A4 B6 2.5 TDI, Engine 180 hp, running unevenly

[Translating...]

Wenn ich von dem Motortyp höre, denke ich spontan an die Nockenwellen...

05-05-2020, 21:41 Subject: A4 B6 2.5 TDI, Engine 180 hp, running unevenly

[Translating...]

die schauen sehr gut aus, zumindest vor einem halben Jahr noch als ich die Düsen neu gemacht habe