I think some vacuum leaks may become bigger or smaller based on temperature. My vacuum reservoir showed a minor leak at times and sometimes it would get bigger.
id make sure you are starting with a good vacuum gauge pump to begin with.
it's also extremely helpful to follow the test schedule in Rheingold where it activates each waste gate and to visually see it move.
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535D Xdrive DUDMD Stage 1
x5d e70 DUDMD stage 2 tune
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