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Old 05-13-2009, 10:37 PM   #1
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Default Fuel cut at 5300rpm?

Here's the issue. Car will run full boost all the way to redline at ~90-95% throttle. But, if I put my foot all the way to the floor, it hits a wall around 5300rpm. AFR's are around 11.3 just before it happens. According to the datalog that I took, it looks like something is cutting fuel at that point. If someone can take a quick look at both files below and let me know if you see anything weird. Please excuse the lack of an AFR reading in the datalog, I am STILL trying to figure our how to get it working correctly.
Attached Files
File Type: msq megasquirt051209.msq (35.2 KB, 82 views)
File Type: xls datalog051209.xls (37.7 KB, 54 views)
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Old 05-13-2009, 10:51 PM   #2
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I'm having some problems with your MSQ, but have you checked the overboost protection setting?
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Old 05-13-2009, 11:26 PM   #3
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Overboost is set at 13 or 14 psi. The gauge is hitting ~12.
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Old 05-14-2009, 10:28 AM   #4
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Hmmm.

What's really bizarre is that not only does fuel drop to 0, but spark drop straight to 10.1 and stays there until you let off the throttle.

Ooh, I've got an idea- try turning off launch control.
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Old 05-14-2009, 10:51 AM   #5
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Hmm, I didn't realize that it was on. If that was the problem, I really need a vacation.

I'll give it a shot tonight and let you know.
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Old 05-14-2009, 11:00 AM   #6
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Quote:
Originally Posted by GT3man2001 View Post
Overboost is set at 13 or 14 psi. The gauge is hitting ~12.
That's close enough for a little bit of noise to trigger it. Raise the overboost protection kPa limit a little bit. The overboost protection feature is rather aggressive and sometimes will even act preemptively if you are both near its limit and the boost is climbing.
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Old 05-14-2009, 11:44 AM   #7
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Will do that too, thanks. Probably raise it to 15psi.
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Old 05-14-2009, 11:03 PM   #8
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One of those fixed the problem. Now I have something mechanical to look for. Seems like it's never ending...
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Old 05-15-2009, 10:13 AM   #9
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One or none?
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Old 05-15-2009, 10:34 AM   #10
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One. I did them both at the same time, so not sure which one fixed it. Probably the overboost.
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