Any time the oxygen sensors/cat are worked on, the long term fuel trim tables (part of the ECU) need to be reset as fixit suggested. It the shop didn't do it, you need to. If these codes come back, then hunt for all of the possible vacuum leaks. The hard-to-find elbow on the left side of the intake manifold is a common culprit, but also check around the vacuum tree, connections to the turbo, etc.

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'96 850 and '83 244 DL both at about 200K; gone but not forgotten '81 245 and '64 Amazon