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[UPP_COS]

So I've been reading these forums, and some people say that you can't MBC, some say you can. Some say NOT with S1, others say OK. And still yet others say YES with S1, but S1 works better without it!

SO, I'm trying to install a TXS-DSMBC on a customers car, and am having little no luck. I found the stock existing boost solnoid valve, and used the "pressure in" as my pressure source, and the brown "to WG" as the out put.... (BTW he has S1 installed already.) Now without the MBC and only S1 he peaks to just above 1Bar, and holds 1Bar relatively all the way till red-line. With the MBC installed (and obviously the stock boost solnoid out of the loop) he peaks at only 1Bar, then drops significantly fast and holds only .5Bar to red-line...

Am I doing something wrong? And without the stock solnoid inline, how is the ecu contoling the boost? Any help would be greatly appreciated.

Sincerely,
CK
UPP
COS, CO