ISCV control system disassembly
Apr 27, 2010, 07:10 PM
#76
Evolving Member
Join Date: May 2008
Location: Dallas, TX
Posts: 346
Likes: 0
Received 0 Likes
on
0 Posts
mrfred... i am running 9653 V7 rom on my car... both SD and non SD... and I have cams... basically most other parts the car is ok and idles fine... but with the AC on if i come to a stop and push in the clutch the revs will drop to about 500rpm then sometimes catch other times it will stall... is there a table that has fixed it.
all the tables are as stock but i changed all the values in the following to 0 to help with rev hang.
1. ISCV Demand RPM Adder [rpm > 4500, load > 170, speed > 12 mph]
2. ISCV Demand RPM Adder (Moderated by Baro, IATS) (FFFF6EA8) (sub_204B6) [sub_1EFC0]
all the tables are as stock but i changed all the values in the following to 0 to help with rev hang.
1. ISCV Demand RPM Adder [rpm > 4500, load > 170, speed > 12 mph]
2. ISCV Demand RPM Adder (Moderated by Baro, IATS) (FFFF6EA8) (sub_204B6) [sub_1EFC0]
Jul 30, 2010, 10:00 PM
#79
Evolved Member
iTrader: (10)
Join Date: Apr 2009
Location: Rio Rancho NM
Posts: 659
Likes: 0
Received 0 Likes
on
0 Posts
Wow this is a great thread, thank you mrfred. After I installed my cams I have been having idle issues. So I will define the tables in ecuflash, but then what adjustments would need to be made in order to correct idle issues? The car wants to stall when coming to a stop, and idle is not stable.
Aug 14, 2010, 02:26 AM
#83
Evolving Member
Are the ISC steps we can see in evoscan a reading of the ISCV position or what the ECU is telling it to do ?
I've got an awful throttle hang like 3-4 seconds
I've got an awful throttle hang like 3-4 seconds
Last edited by Kakihara; Aug 14, 2010 at 02:38 AM.
Sep 21, 2010, 12:22 AM
#86
For anyone curious, I have these tables in the "Idle" section of my XML (not sure where I got them) and they match the addresses just below that MrFred posted from his disassembly.
Desired ISCV initial step position with AC off-Drive
Desired ISCV initial step position with AC on-Neutral
"ISCV Demand CTS Adder #1** (sub_1F1F8, sub_1EA0C, sub_1F596) [sub_1EFC0]"
"ISCV Demand CTS Adder #1b*** (sub_1F2C6) [sub_1EFC0]" category="ISCV Control"
I'm not sure if MrFred defined them as such or if those labels are even correct. They did seem to add quite a bit to my ISCV demand when I modified them before.
Desired ISCV initial step position with AC off-Drive
Desired ISCV initial step position with AC on-Neutral
"ISCV Demand CTS Adder #1** (sub_1F1F8, sub_1EA0C, sub_1F596) [sub_1EFC0]"
"ISCV Demand CTS Adder #1b*** (sub_1F2C6) [sub_1EFC0]" category="ISCV Control"
I'm not sure if MrFred defined them as such or if those labels are even correct. They did seem to add quite a bit to my ISCV demand when I modified them before.
Desired ISCV initial step position with AC off-Neutral
Desired ISCV initial step position with AC on-Neutral
Have the same addys as
"ISCV Demand CTS Adder #1** (sub_1F1F8, sub_1EA0C, sub_1F596) [sub_1EFC0]"
"ISCV Demand CTS Adder #1b*** (sub_1F2C6) [sub_1EFC0]" category="ISCV Control"
What about "Desired ISCV initial step position with AC off-Drive"? Is it never used?
Sep 21, 2010, 01:59 AM
#87
I've always been curious about the neutral/drive thing that was put into the early definition names. I've never seen anything in the ROM code that attempts to establish a neutral/drive condition (not so easy in a manual tranny vehicle and not so obvious why it would be needed). They could be interpreting the clutch switch as neutral/drive. I'll try to take a look soon.
Sep 21, 2010, 03:46 AM
#88
Anymore on this. I also noticed that both
Desired ISCV initial step position with AC off-Neutral
Desired ISCV initial step position with AC on-Neutral
Have the same addys as
"ISCV Demand CTS Adder #1** (sub_1F1F8, sub_1EA0C, sub_1F596) [sub_1EFC0]"
"ISCV Demand CTS Adder #1b*** (sub_1F2C6) [sub_1EFC0]" category="ISCV Control"
What about "Desired ISCV initial step position with AC off-Drive"? Is it never used?
Desired ISCV initial step position with AC off-Neutral
Desired ISCV initial step position with AC on-Neutral
Have the same addys as
"ISCV Demand CTS Adder #1** (sub_1F1F8, sub_1EA0C, sub_1F596) [sub_1EFC0]"
"ISCV Demand CTS Adder #1b*** (sub_1F2C6) [sub_1EFC0]" category="ISCV Control"
What about "Desired ISCV initial step position with AC off-Drive"? Is it never used?
The "Desired ISCV initial step position with AC off-Drive" table is the "ISCV Demand Adder #1** (sub_1F1F8, sub_1EA0C, sub_1F596) [sub_1EFC0]" table.
The "Desired ISCV intial step position with AC off-Neutral" is actually the minimum idle vs coolant temp table with the wrong units applied to it.
The "Desired ISCV intial step position with AC on-Neutral" table is the ""ISCV Demand Adder #1b*** (sub_1F2C6) [sub_1EFC0]" table.
Looking quickly at my disassem, the two original tables that are ISCV Demand tables are related to AC on/off status, but it looks like the original tables have the status reversed.
Sep 21, 2010, 12:21 PM
#89
I took a look. Guess I'll start by saying that many of the old definitions for ECUFlash are pretty far off the mark. Consider the old knock tables. I don't think that any of those tables had anything to do with knock. The ISCV stuff is not much better.
The "Desired ISCV initial step position with AC off-Drive" table is the "ISCV Demand Adder #1** (sub_1F1F8, sub_1EA0C, sub_1F596) [sub_1EFC0]" table.
The "Desired ISCV intial step position with AC off-Neutral" is actually the minimum idle vs coolant temp table with the wrong units applied to it. also do you know what the correct units are for this.
The "Desired ISCV intial step position with AC on-Neutral" table is the ""ISCV Demand Adder #1b*** (sub_1F2C6) [sub_1EFC0]" table.
Looking quickly at my disassem, the two original tables that are ISCV Demand tables are related to AC on/off status, but it looks like the original tables have the status reversed.
The "Desired ISCV initial step position with AC off-Drive" table is the "ISCV Demand Adder #1** (sub_1F1F8, sub_1EA0C, sub_1F596) [sub_1EFC0]" table.
The "Desired ISCV intial step position with AC off-Neutral" is actually the minimum idle vs coolant temp table with the wrong units applied to it. also do you know what the correct units are for this.
The "Desired ISCV intial step position with AC on-Neutral" table is the ""ISCV Demand Adder #1b*** (sub_1F2C6) [sub_1EFC0]" table.
Looking quickly at my disassem, the two original tables that are ISCV Demand tables are related to AC on/off status, but it looks like the original tables have the status reversed.