[cmcacmca75]

Doing a boost leak test on my 2013 535i, I notice that the Suction Jet line (for the fuel tank breather valve) is T'ed between the charge pipe and turbo inlet pipe (by the crankcase vent).

Can someone explain to me how boosting is efficient if there is this 1/2" line between the two? Wouldn't boost in the charge pipe also get feed back into the turbo inlet. I don't think there is a check valve inline preventing boost from traveling this way, and if there is mine must be broken because pressure flows to the turbo inlet side (in non-turbo boost leak configuration).

I have slow boost rate and fall 3 PSI short of target. Vacuum system good, pwg solenoid good, all boost seals replaced, new pure turbo stage 2 with GFB+ upgraded diverter.