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Old 06-06-2005, 04:17 AM   #1
WolfDrive
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Default Hit fuel cut... should I raise it?

I've got a TD06/20G with catless TBE, perrin injectors, walbro fuel pump, BigMAF intake, APS FMIC, STi UTEC, etc.etc...

Recently I've been hitting fuel cut a lot -- it's set at 24, though I seem to be hitting it ~20 (according to the logs). [my EBC read 24.2psi] My IDC's seem fine and dandy at 55-60 -- though I dont know why at the end of this log clip they hold at 59.3 -- and I'm getting zero knock throughout the map...

sooo is it safe to raise the fuel cut ? BTW: running on 93 pump

Code:
 3095, -3.6,2.4, 22, 00,   00,  +46.0,   8.7,ECU. , -1.0,ECU.  ,2.3, 14.65
 3135, -4.0,2.3, 21, 00,   00,  +46.0,   8.1,ECU. , -1.3,ECU.  ,2.2, 14.83
 3132, -5.1,1.7,  0, 00,   00,  +38.9,   7.6,ECU. , -1.0,ECU.  ,1.5, 15.08
 3092, -6.7,1.5,  0, 00,   00,  +31.8,   7.6,ECU. , -0.8,ECU.  ,1.4, 13.45
 2981, -8.7,1.5,  0, 00,   00,  +25.6,   7.6,ECU. , -1.8,ECU.  ,1.4, 12.37
 2705,-10.2,2.0, 23, 10,   00,  +35.5,   7.0,ECU. , +2.2,ECU.  ,2.3, 13.12
 2467, -9.6,2.4, 27, 10,   00,  +44.6,   9.7,ECU. , +2.0,ECU.  ,2.4, 14.18
 2447, -7.3,2.4, 28, 10,   00,  +42.1,   9.8,ECU. , +2.0,ECU.  ,2.4, 14.74
 2485, -5.1,2.5, 28, 10,   00,  +41.6,   9.9,ECU. , +2.3,ECU.  ,2.4, 15.18
 2519, -2.8,2.5, 28, 10,   00,  +39.8,  11.0,ECU. , +2.5,ECU.  ,2.5, 15.31
 2554, -2.0,2.5, 28, 10,   00,  +39.4,  11.3,ECU. , +2.4,ECU.  ,2.5, 15.02
 2592, -1.8,2.5, 28, 10,   00,  +39.7,  11.5,ECU. , +2.3,ECU.  ,2.5, 14.83
 2635, -1.6,2.6, 28, 10,   00,  +39.4,  12.1,ECU. , +2.3,ECU.  ,2.5, 14.87
 2668, -1.4,2.6, 29, 10,   00,  +39.3,  12.0,ECU. , +2.2,ECU.  ,2.6, 15.02
 2723, -1.0,2.7, 32, 10,   00,  +36.7,  13.8,ECU. , +2.1,375.00,2.6, 15.12
 2791, -0.2,2.8, 33, 10,   00,  +34.8,  15.6,ECU. , +1.8,375.00,2.7, 15.24
 2812, +0.6,2.8, 33, 10,   00,  +33.8,  16.0,ECU. , +1.3,375.00,2.7, 14.49
 2878, +1.5,2.8, 33, 20,   00,  +33.8,  16.7,ECU. , -0.3,375.00,2.7, 13.65
 2952, +2.1,2.9, 35, 20,   00,  +34.3,  17.6,ECU. , -0.6,375.00,2.8, 13.47
 3033, +2.9,3.0, 35, 20,   00,  +33.6,  18.8,ECU. , -1.0,375.00,2.9, 13.50
 3089, +3.7,3.0, 38, 30,   00,  +33.4,  19.2,ECU. , -2.1,375.00,2.9, 13.23
 3171, +4.7,3.2, 45, 30,   00,  +31.5,  22.2,ECU. , -2.7,375.00,3.0, 12.99
 3248, +6.4,3.3, 47, 40,   00,  +25.9,  24.2,+23.0, -3.5,375.00,3.0, 12.96
 3333, +7.8,3.4, 48, 50,   00,  +23.6,  25.5,+17.0, -2.8,375.00,3.2, 12.61
 3439, +9.6,3.5, 48, 50,   00,  +19.7,  30.0,+17.0, -2.9,375.00,3.3, 12.14
 3505,+11.7,3.7, 45, 60,   00,  +15.7,  35.9,+16.0, -1.4,375.00,3.6, 11.68
 3667,+13.9,3.9, 44, 70,   00,  +12.0,  43.7,+14.0, -1.5,375.00,3.7, 11.14
 3792,+16.8,4.0, 42, 90,   00,   +9.3,  49.8,+14.0, -1.7,375.00,3.8, 10.86
 3898,+19.6,4.1, 38,100,   00,   +9.0,  49.7,+14.0, -2.0,375.00,2.8, 10.48
 4480,+20.2,3.8, 36, 90,   00,  +20.1,  55.3,+15.1, -3.7,375.00,3.8, 11.30
 4030,+17.0,3.2,  0, 00,   00,  +23.7,  59.3,ECU. , -6.0,ECU.  ,2.5, 11.30
 3770, +9.6,2.2,  0, 00,   00,  +23.5,  59.3,ECU. , -4.6,ECU.  ,2.1, 10.96
 3415, +0.8,2.1,  0, 00,   00,  +23.7,  59.3,ECU. , -2.8,ECU.  ,2.0, 12.99
 3245, -6.1,1.3,  0, 00,   00,  +23.7,  59.3,ECU. , -1.8,ECU.  ,1.2, 14.92
 3046,-10.2,1.3,  0, 00,   00,  +23.7,  59.3,ECU. , -0.4,ECU.  ,1.2, 14.87
 2754,-11.0,1.3,  4, 00,   00,  +24.0,  59.3,ECU. , -0.3,ECU.  ,1.3, 19.71
 2460,-11.0,1.4,  0, 00,   00,  +23.9,  59.3,ECU. , +0.0,ECU.  ,1.4, >25:1
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Old 06-06-2005, 09:23 AM   #2
west005
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What EM? TurboXS and some others sell fuel cut defender. Asking them would be safer. Call TurboXS, Nathan is pretty cool and should be helpful.
Later
E
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Old 06-06-2005, 09:28 AM   #3
Davenow
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Quote:
Originally Posted by west005
What EM? TurboXS and some others sell fuel cut defender. Asking them would be safer. Call TurboXS, Nathan is pretty cool and should be helpful.
Later
E
he said utec

and the utec doesnt need a fuel cut defender, its built in.
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Old 06-06-2005, 09:32 AM   #4
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I did not open my eyes, but yeah I would call TurboXS VS NASIOC posts. Unless one of the tuners jumps in.
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Old 06-06-2005, 09:33 AM   #5
happasaiyan
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change your UTEC boost display to "gauge".

you will see that you are actually running 24psi. so...if its safe right now, then sure, go ahead and raise it.
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Old 06-06-2005, 09:42 AM   #6
serendipity
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The MAP sensor is slow in UTEC logs. You're probably hitting 24psi, but not long enough for it to show up in the logs. Is there a problem with your wastegate? You may have blown a hose off the wastegate actuator, which would cause the behavior your seeing - it'll overboost all the time. Double check your hoses. If they're fine, you have to decide how much boost you're comfortable with, and set your boost map (or other boost controller) accordingly. I would set fuel cut for 1-2psi above what you plan to peak at. If you plan to peak at 20psi, set fuel cut for 22psi, etc.

The ECU shuts off the fuel pump at 0% throttle when you're coasting down, and it leaves the IDCs at whatever their last value was, so it's normal for it to say 59.3 the whole way down. Note that your AFRs will go to >25:1 since there's no fuel (no actual combustion happening).
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Old 06-06-2005, 09:45 AM   #7
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Quote:
Originally Posted by happasaiyan
change your UTEC boost display to "gauge".

you will see that you are actually running 24psi. so...if its safe right now, then sure, go ahead and raise it.
He is displaying gauge - there's a bug where it always says psia. Note the negative values when he's in vacuum
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Old 06-06-2005, 10:29 AM   #8
wrex03
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Your "cars" timing is very low in this range (3600-3800). Is this were you normaly hit fuel cut?

Code:
3333, +7.8,3.4, 48, 50,   00,  +23.6,  25.5,+17.0, -2.8,375.00,3.2, 12.61
 3439, +9.6,3.5, 48, 50,   00,  +19.7,  30.0,+17.0, -2.9,375.00,3.3, 12.14
 3505,+11.7,3.7, 45, 60,   00,  +15.7,  35.9,+16.0, -1.4,375.00,3.6, 11.68
 3667,+13.9,3.9, 44, 70,   00,  +12.0,  43.7,+14.0, -1.5,375.00,3.7, 11.14
 3792,+16.8,4.0, 42, 90,   00,   +9.3,  49.8,+14.0, -1.7,375.00,3.8, 10.86
 3898,+19.6,4.1, 38,100,   00,   +9.0,  49.7,+14.0, -2.0,375.00,2.8, 10.48
 4480,+20.2,3.8, 36, 90,   00,  +20.1,  55.3,+15.1, -3.7,375.00,3.8, 11.30
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Old 06-06-2005, 12:00 PM   #9
x99percent
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I'm not sure if you've done this already or not, but FYI:

You need to flip the FCD switch on the UTEC if you want to run >20psi, because the factory ECU is shutting down the fuel pump in an attempt to stop the overboosting.

The switch corresponds to two settings for the UTEC's hardware FCD.
1 - Move the factory fuel cut from ~17psi to ~20.5psi
2 - Eliminate the factory fuel cut altogether.

This switch has *nothing* to do with the UTEC's software-based fuel cut in the OLF parameters.
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Old 06-06-2005, 12:05 PM   #10
serendipity
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Good catch - I forgot about the UTEC's toggle switch. That's probably what he's hitting.
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Old 06-06-2005, 12:32 PM   #11
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if the FCD isnt turned on, your car will just run lean. it wont feel like a typical fuel cut.

ie- if software boost cut is > FCD, when FCD boost cut < current boost < software boost cut, you will run ridiculously lean.

when i was setting boost higher and tuning for the higher boost, before i flipped the FCD switch (or even knew i had to), i had the software boost cut at 25psi...and was running 22-23psi...and 13:1AFR (when it would shut off the fuel pump). this doesnt look to be the case here.

also- before i switched my UTEC boost display to gauge, it would only show 19-20psi or so...then set it to gauge, and voila 22-23...which is what my defi boost gauge had been showing me all along.
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Old 06-06-2005, 12:57 PM   #12
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Quote:
Originally Posted by happasaiyan
also- before i switched my UTEC boost display to gauge, it would only show 19-20psi or so...then set it to gauge, and voila 22-23...which is what my defi boost gauge had been showing me all along.

I had the same issue...
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