A4 (B5 Platform) Discussion Discussion forum for the B5 Audi A4 produced from 1995-2001 B5 FAQ

MBC issues...

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Old Aug 16, 2007 | 08:20 AM
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AEBlessed (1.8G)'s Avatar
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Default MBC issues...

I posted a couple of days ago that I was experiencing throttle cut under acceleration and full boost. I played around with the mbc a little bit, and it seems that the "throttle cut" occurs when my boost reaches its limit as dictated by the mbc. Is this a wastegate issue? I have heard that the GTRS wastegate is crap. It pretty much feels like i am running into a rev limiter or something, I am starting to get pretty frustrated. Has anybody experienced anything similar?
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Old Aug 16, 2007 | 08:20 AM
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what kind of boost are you trying to run.. what software... do you have a clamp on the boost sensor?
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Old Aug 16, 2007 | 08:23 AM
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I have been running 20psi on unitronics tuning. Where is the boost sensor?
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Old Aug 16, 2007 | 08:50 AM
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Default What is the software requesting? If you are trying ot make more then its requesting

by using the manual boost controller you may be hitting a boost cut that is slamming the TB shut or opening the DV.
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Old Aug 16, 2007 | 08:57 AM
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IIRC, the software requests 19psi but can be cranked up via mbc...
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Old Aug 16, 2007 | 09:30 AM
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you need to log and check requested boost and see.
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Old Aug 16, 2007 | 09:38 AM
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Default I am gonna order the VAG software after I pay tuition... priorities.

Does anyone know which version to order with the ebay cable?
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Old Aug 16, 2007 | 03:11 PM
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Default Your car looks like a 98 or 99 right?

You're nDBW, so you don't have a MAP sensor.
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Old Aug 16, 2007 | 03:29 PM
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yeah, its a 99
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Old Aug 17, 2007 | 05:47 AM
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Default Ah yes, should have read the name... AEB duh!!!

still no 1.8t has a map sensor really.. as its not in the manifold, its just a boos reference sensor.

will go back and check your OP to see if I have any other ideas.
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