Nadir Point is refering to finding a boost leak in your intake tract, you can pressurize it trough a meth port if you have one to find a boost leak.
OP is talking about finding leaks in vacuum system. you wan to use a vacuum pump for that.
another idea is have you reset maf adaptations?
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535D Xdrive DUDMD Stage 1
x5d e70 DUDMD stage 2 tune
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