Bad news, new valve seals won't help you! It's a well known issue with the 4,2 engines, especially the first couple of thousands. The common procedure is to replace the engine by an AEC from an S6, the conversion is comparable stressless.

I don't wanna disenchant you, but you save a lot of money when you don't start to change valve seals or stuff like that in order to significantly reduce the oil consumption. It won't work out (you are by far not the first one trying)!

How far away are you from Elmsland? We've an expert there, unfortunately he is a physically a bit handicapped at the moment, but he would definetely help you on switching the engine when he is restored again, I'm sure.

Regards

Bastian

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