So charge pressure control pos. deviation doesn't necessarily mean a boost leak? After STFA I found
09-12-2006, 09:37 AM
#11
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weird
for the longest time i had thought it was the other way around, after something i read.
i always thought it was stupid and counterintuitive - "positive" meaning "requested" was higher than actual.
i always thought it was stupid and counterintuitive - "positive" meaning "requested" was higher than actual.
09-12-2006, 09:39 AM
#12
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Thanks a ton for all the help guys. If indeed I was ramping up boost faster than x-chip wants to
see, is there any reason it took over a year for the ecu to throw this code? I know the ecu will obviously adapt over time, but would it take a full year??
09-12-2006, 09:41 AM
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There really isn't a "problem" if you run MBC only. You'll see the code, but it has no effect.
If you run N75, you'll go limp. That was the initial reason I went from MBC in parallel to MBC alone on my K04/K16s.
09-12-2006, 10:02 AM
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No, the MBC tries to reach your pre-set boost level at any throttle position...
meaning the wastegates are shut. You don't actually reach your pre-set boost level at low partial throttle inputs because there isn't enough exhaust gas energy available to feed the turbos.
09-12-2006, 10:03 AM
#18
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Sorry, you're technically correct but "request isn't met" most of the time.
I can see how it would be at high RPM part throttle like you've explained in the past, though.
P.S.-00blackS4, nice 2nd car you've got there.
P.S.-00blackS4, nice 2nd car you've got there.
09-12-2006, 10:27 AM
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Midgie needs to back to school. :-P
That's why the boost is "requested". That doesn't have any bearing on if that requested boost is met or not. Boost request is what controls the wastegates. Exhaust gas energy is what controls the actual boost.
An MBC is basically an on/off device.
An MBC is basically an on/off device.