Audi A4 Rough Engine: Causes & Fixes

Hello everyone,
My little Audi A4/B5 AHH is giving me some cause for concern.
I have the impression that it always runs "something" rougher than it should.
He does this both when the engine is idling and while driving.

Therefore, my question is: can anyone recommend someone in Bavaria who can perform a specific diagnosis?

Changing parts like a world champion... yes, I can do that myself .

Thank you in advance for all responses.
Best regards,
Peter

Audi A4, model AHH, year 1999, 260,000 km.

I can't recommend a specific workshop, but you could check the free-running clutch on the alternator. It's not a big deal, but it can definitely cause unpleasant vibrations.

I have removed the second identical post.
Tobias' suggestion is an interesting option; otherwise, a diagnostic system should be considered.
hg
Herbert.

ok, thank you for the information.
Years ago, I had a similar problem with the freewheel on a Mercedes-Benz S210 300TDT. It was a terrible job to replace it; it required special tools, and it was extremely difficult to remove.

I will report on what happened with that matter.

Best regards, Peter.