Yesterday's Technology at Today's Prices
01-13-2005, 04:53 PM
#47
Token Toyota Mod
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Originally Posted by sperry
Hey dude... want a UniChip?
All you need is a MBC (I got one of theose just lying around too), an up-pipe, TBE and you should be good to go w/ my crappy engine management!
Serously, I'd sell the MBC (it's a nice TurboXS screw-adjustable one) and the UniChip/EFi/Harness for like $100.
...assuming you can run an MBC on your car. I hear rumors that '04+ cars straight up can't use 'em.... Aaron?
All you need is a MBC (I got one of theose just lying around too), an up-pipe, TBE and you should be good to go w/ my crappy engine management!
Serously, I'd sell the MBC (it's a nice TurboXS screw-adjustable one) and the UniChip/EFi/Harness for like $100.
...assuming you can run an MBC on your car. I hear rumors that '04+ cars straight up can't use 'em.... Aaron?
01-13-2005, 05:08 PM
#49
Warm Fuzzy Admin
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IIRC, open-loop delay = really, really bad partial throttle, full boost if the ECU isn't managing stuff. It doesn't start dumping fuel (open-loop) soon enough to prevent issues if you're running more boost than stock, since the closed maps assume you're running at a certain boost level when you're actually higher.
EPA voodoo to keep from dumping fuel into the motor when its not necessary.
Partial throttle, full boost = slagged pistons
EPA voodoo to keep from dumping fuel into the motor when its not necessary.
Partial throttle, full boost = slagged pistons
01-13-2005, 05:12 PM
#50
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Car Info: '94 SVX, '02 WRX
Originally Posted by Aaron@S-S
IIRC, open-loop delay = really, really bad partial throttle, full boost if the ECU isn't managing stuff. It doesn't start dumping fuel (open-loop) soon enough to prevent issues if you're running more boost than stock, since the closed maps assume you're running at a certain boost level when you're actually higher.
EPA voodoo to keep from dumping fuel into the motor when its not necessary.
Partial throttle, full boost = slagged pistons
EPA voodoo to keep from dumping fuel into the motor when its not necessary.
Partial throttle, full boost = slagged pistons
I can see how that's bad.
01-13-2005, 05:20 PM
#51
Warm Fuzzy Admin
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Originally Posted by sperry
So basically, there's a delay between close to open loop switching that can mean the car is at full boost in closed-loop for longer than the simple parial throttle conditions we were seeing on the 02-03 WRXs?
I can see how that's bad.
I can see how that's bad.
Yeah, like 1-2 seconds. Injectors go from <60% duty cycle at full throttle at high RPM to ~90%, but only after a significant delay; EGT's shoot up to almost 1700 degrees, AFR's are like 14.5+
Bad stuff. I guess more accurately would be partial fueling, full boost, but that's basically throttle anyways.
They're trying to minimize open-loop conditions. A reflash from a good tuner (
)will eliminate the issue, because the closed-loop maps are more accurate, and open-loop parameters are adjusted.
01-13-2005, 05:21 PM
#52
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Originally Posted by Aaron@S-S
Yeah, like 1-2 seconds. Injectors go from <60% duty cycle at full throttle at high RPM to ~90%, but only after a significant delay; EGT's shoot up to almost 1700 degrees, AFR's are like 14.5+
Bad stuff. I guess more accurately would be partial fueling, full boost, but that's basically throttle anyways.
They're trying to minimize open-loop conditions. A reflash from a good tuner ()will eliminate the issue, because the closed-loop maps are more accurate, and open-loop parameters are adjusted.
Bad stuff. I guess more accurately would be partial fueling, full boost, but that's basically throttle anyways.
They're trying to minimize open-loop conditions. A reflash from a good tuner (
)will eliminate the issue, because the closed-loop maps are more accurate, and open-loop parameters are adjusted.
01-13-2005, 05:28 PM
#53
Warm Fuzzy Admin
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Originally Posted by sperry
Is that just an attempt to get better mileage results? Or is that a side effect of going to the fly-by-wire throttle?
01-13-2005, 05:31 PM
#54
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Originally Posted by Aaron@S-S
More about mileage, as the DBW doesn't add more than .25ms tot he response time; it's enough that you notice it going from a DBW to a cable-driven car, but not on the same scope we're talking here.
01-13-2005, 05:39 PM
#55
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Originally Posted by sperry
I thought it might be an issue w/ the DBW programming in the ECU, not so much a delay due to the computer actuating the throttle.
02-26-2005, 09:45 PM
#57
the artist formerly known as mcdrama
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bump this, I want more info on this. Where did this open/closed loop information source from? I have seen a lot of posts on forums about this, but after googling, I can not find a reliable source of the bad side effects of this open/closed loop.
I just have a catless uppipe in my 04 wrx wagon and after 12K miles I am getting CELs P0544/P0546. I am thinking of getting EcuTek tuned after learning about this, assuming its true. =x
I just have a catless uppipe in my 04 wrx wagon and after 12K miles I am getting CELs P0544/P0546. I am thinking of getting EcuTek tuned after learning about this, assuming its true. =x
02-26-2005, 10:16 PM
#59
the artist formerly known as mcdrama
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Originally Posted by RussB
there's a sticky in the 2.0l forum over on nabisco all about it. engine management will fix the problem.