ISCV control system disassembly
#151
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So, is ISC Steps at Request 16 like "STFT" and 08 and 0A are like "LTFT" but for ISCV demand instead of injectors? Or is ISC Steps more like IPW maybe, since it's an exact measure not a "plus or minus some amount" measurement? I guess I'm trying to think how I'll use this to set my ISCV values to get my idle ironed out. Since I am switching from a totally different engine's rom to the Tephra stuff, what I'm starting with was way way off.
Also...you'd like ISCV Demand Trims to be close to 0 I'd assume, right?
Also...you'd like ISCV Demand Trims to be close to 0 I'd assume, right?
#153
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So I loaded those defs into evoscan (running 9417 V7) and logged them.
The ac off trim moved from -8 to -10
The ac on trim was static at -56
So, if I read this correctly, I need to pull 8-10 ISCV steps from one of the ISCV tables, question is, which ones???
Logs attached, ac off, ac on, both with some free rev MAF induced low RPM stumbling at the end of each log, just to remind me it's still present.
The ac off trim moved from -8 to -10
The ac on trim was static at -56
So, if I read this correctly, I need to pull 8-10 ISCV steps from one of the ISCV tables, question is, which ones???
Logs attached, ac off, ac on, both with some free rev MAF induced low RPM stumbling at the end of each log, just to remind me it's still present.
#154
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So I loaded those defs into evoscan (running 9417 V7) and logged them.
The ac off trim moved from -8 to -10
The ac on trim was static at -56
So, if I read this correctly, I need to pull 8-10 ISCV steps from one of the ISCV tables, question is, which ones???
Logs attached, ac off, ac on, both with some free rev MAF induced low RPM stumbling at the end of each log, just to remind me it's still present.
The ac off trim moved from -8 to -10
The ac on trim was static at -56
So, if I read this correctly, I need to pull 8-10 ISCV steps from one of the ISCV tables, question is, which ones???
Logs attached, ac off, ac on, both with some free rev MAF induced low RPM stumbling at the end of each log, just to remind me it's still present.
#155
So I loaded those defs into evoscan (running 9417 V7) and logged them.
The ac off trim moved from -8 to -10
The ac on trim was static at -56
So, if I read this correctly, I need to pull 8-10 ISCV steps from one of the ISCV tables, question is, which ones???
Logs attached, ac off, ac on, both with some free rev MAF induced low RPM stumbling at the end of each log, just to remind me it's still present.
The ac off trim moved from -8 to -10
The ac on trim was static at -56
So, if I read this correctly, I need to pull 8-10 ISCV steps from one of the ISCV tables, question is, which ones???
Logs attached, ac off, ac on, both with some free rev MAF induced low RPM stumbling at the end of each log, just to remind me it's still present.
Last edited by mrfred; Sep 9, 2011 at 09:22 AM.
#158
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I logged my iscv demand and got -7% to -11%.
Would it be easier to just close the biss down in order for the iscv to open up more and bring the trims closer to 0%? or should i tweak the tables?
Also, how can i reset the trims without unplugging the battery?
Attached is a log i just took.
Would it be easier to just close the biss down in order for the iscv to open up more and bring the trims closer to 0%? or should i tweak the tables?
Also, how can i reset the trims without unplugging the battery?
Attached is a log i just took.
Last edited by hyeteck; Sep 9, 2011 at 02:34 PM.
#159
Looks like these
Are now Throttle Percentage where before they were Load.
PHP Code:
<table name="ISCV Demand TPS Adder, AC off (FFFF6E84) (mattjin fuel cut delay)" category="Idle" address="3d6e" type="2D" level="1" scaling="ISCV_AX2_8">
<table name="TPS" address="6f9a" type="Y Axis" elements="7" scaling="ThrottlePercentage"/>
</table>
<table name="ISCV Demand TPS Adder, AC on (FFFF6E84) (mattjin fuel cut delay)" category="Idle" address="3d82" type="2D" level="1" scaling="ISCV_AX2_8">
<table name="TPS" address="6f9a" type="Y Axis" elements="7" scaling="ThrottlePercentage"/>
</table>
#160
Looks like these
Are now Throttle Percentage where before they were Load.
PHP Code:
<table name="ISCV Demand TPS Adder, AC off (FFFF6E84) (mattjin fuel cut delay)" category="Idle" address="3d6e" type="2D" level="1" scaling="ISCV_AX2_8">
<table name="TPS" address="6f9a" type="Y Axis" elements="7" scaling="ThrottlePercentage"/>
</table>
<table name="ISCV Demand TPS Adder, AC on (FFFF6E84) (mattjin fuel cut delay)" category="Idle" address="3d82" type="2D" level="1" scaling="ISCV_AX2_8">
<table name="TPS" address="6f9a" type="Y Axis" elements="7" scaling="ThrottlePercentage"/>
</table>
#162
Wondering which table i should be tweaking in 9653 rom. Im getting idle surge on decel. Basically clutch in and coasting down. Once below im guessing 5mph the idle stabilizes. This is definitely speed dependent. Once below 5mph (my best guess) the idle is where it should be. Moving faster than that it surges to 1500 or so then back down. As soon as im below a specific mph it drops to where it should be.
#163
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I've been logging ISCV trims, and it's really helped me to sort of iron it out, but only for the fully warmed up values.
I have one question that may help me iron it out at "not fully warm" levels. What is the temp axis on the idle stepper table? I know the def says "temp", but is that temp C, or F, or something else (like a different kind of temp scaling), because one of the guys I interface with regularly pointed out that 100degrees is pretty cool if it's F, but that's what my definition say sit is.
I have one question that may help me iron it out at "not fully warm" levels. What is the temp axis on the idle stepper table? I know the def says "temp", but is that temp C, or F, or something else (like a different kind of temp scaling), because one of the guys I interface with regularly pointed out that 100degrees is pretty cool if it's F, but that's what my definition say sit is.
#164
I've been logging ISCV trims, and it's really helped me to sort of iron it out, but only for the fully warmed up values.
I have one question that may help me iron it out at "not fully warm" levels. What is the temp axis on the idle stepper table? I know the def says "temp", but is that temp C, or F, or something else (like a different kind of temp scaling), because one of the guys I interface with regularly pointed out that 100degrees is pretty cool if it's F, but that's what my definition say sit is.
I have one question that may help me iron it out at "not fully warm" levels. What is the temp axis on the idle stepper table? I know the def says "temp", but is that temp C, or F, or something else (like a different kind of temp scaling), because one of the guys I interface with regularly pointed out that 100degrees is pretty cool if it's F, but that's what my definition say sit is.
#165
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So I started messing with the ISCV demand readings on our 95% bone stock evo 8 to get some base numbers.
The first thing I tried to do was set the BISS with Evoscan to 850 rpm per instructions someone posted from some service manual. Doing so would force the idle to rev up to about 1000 rpm when the actuator was disabled but there was not enough ISC adjustment to bring the idle back down but it stopped around 930 rpm(I waited until the ISC Steps in evoscan wouldn't go any lower).
So I decided to adjust the BISS without activating the actuator test in evoscan until I was reading 0% ISCV Demand. Once it reached 0%, I then activated the evoscan BISS actuator test and it reads 750rpm on the nose. I'm assuming this is actually a better BISS target than 850prm?
I also noticed that the ISCV Demand % would adjust itself every 30-60 seconds.
With ISCV Demand at 0%, my ISC Steps at idle with all electrical accessories off (including the radiator fan) reads 22 steps, just as a reference for anyone else.
I'm not sure if any of this is useful to anyone but I figured I would share.
-Jamie
(aka Jack_of_Trades)
- AC and all electrical items are off
- Target idle is 850rpm
- Base ISC Step at operating temp is 7
The first thing I tried to do was set the BISS with Evoscan to 850 rpm per instructions someone posted from some service manual. Doing so would force the idle to rev up to about 1000 rpm when the actuator was disabled but there was not enough ISC adjustment to bring the idle back down but it stopped around 930 rpm(I waited until the ISC Steps in evoscan wouldn't go any lower).
So I decided to adjust the BISS without activating the actuator test in evoscan until I was reading 0% ISCV Demand. Once it reached 0%, I then activated the evoscan BISS actuator test and it reads 750rpm on the nose. I'm assuming this is actually a better BISS target than 850prm?
I also noticed that the ISCV Demand % would adjust itself every 30-60 seconds.
With ISCV Demand at 0%, my ISC Steps at idle with all electrical accessories off (including the radiator fan) reads 22 steps, just as a reference for anyone else.
I'm not sure if any of this is useful to anyone but I figured I would share.
-Jamie
(aka Jack_of_Trades)
Last edited by Dynotech Tuning; Nov 17, 2011 at 12:15 PM.