I have a 1998 A6 32v. It starts itermittently and stalls after warmed up. It always starts when cold. The first mechanic replaced the engine speed sensor (dealer part). That seemed to reduce the problem, but not stop it. There were no other codes.
I took it to an Audi specialist, he could not find any other issue, but the engine speed sensor code came back. He said he has seen new parts fail or not work. I am going to take it back to the original guy and he is going to call dealer. I guess we might as well get a new part and try that. But somehow I don't think that is going to solve the problem.
Any other suggestions?