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Mbc + 90f + Ecu Control = Lower Boost?


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Okay last week it was 70 degrees and now this week it's 90+ degrees. I installed my boost controller between the wastegate actuator line(the easy way) so that the ECU technically still has some control. Could the ECU possibly restrict boost because my MBC is closed all the way to allow maximum boost and at full throtle I'll boost to 15 and then fall back to 10 within a few seconds. If I go like half throttle the turbo will spool to 15psi and sometimes hit fuel cut if I don't let off but it does go to 15 but it won't hold through RPMs like at all. Could it be the ECU or should I install the MBC with the manifold pressure line on one end and then then vaccum hose to the wastegate actuator and cap the BCS intake hose?

Thanks in advance

-Jeff

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you really need to watch with that "part throttle, full boost" situation. if you think about it, the ECU which controls injector duty cycle, wastegate duty, injector pulse, and everything in between...is seeing only partial throttle. the bad part is that your MBC is giving you a much larger boost spike than you really should be unless properly tuned for. full boost with the ECU telling the injectors that they don't need to dump fuel(as it would when you are WOT and full boost) is a recipe for detonation and things can go badly when you run lean multiple times.

ptfb=bad juju

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Well it slowly rises to 15 pounds of boost if I go like half throttle but then when I take it WOT it goes down within a few seconds to 10 and then then it shifts it'll go to about 12psi and then fall to 10 and I'm not sure if it's the hot weather or just not boosting good. I've put my MBC all the way open and I still don't boost high. I'm wondering if the EBC isn't holding boost or something, I want to check it with a hand pump but I don't have one and they're like $30.00. I'm going to set the MBC up the other way without just teeing into the wastegate line and see if it makes a difference. I don't care so much that I'm not boosting high but that I'm not boosting properly.

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I checked the hole and it's clear. Also saw that a Bic Pen spring won't work so scratch that and I'm going to re-install the MBC with the throttle pressure hose going to the wastegate actuator line and see if that doesn't recover anything. Thanks for your help though.

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