domyz

iTrader: (6)

I finally left the Demand% tables alone. What I played with is main demand and initial steps position. Yours may be harder to tune because of cams.
What looks your AC initial step position? (not sure the name of this table on a IX)

Raptord

iTrader: (10)

Here are my ISCV tables (click to enlarge):



Regarding the AC issue: I initially noticed in my log that when I turned on AC while idling the demand went up by ~18%:



So I checked the AC OFF and AC ON tables to see where the biggest difference was. I found it in the TPS Adder, where the value at 13% TPS for AC OFF was 2.7 and for AC ON was 14.9. I brought that down to 7.8 to see how things would change, but demand went up to the same 29.x went I tried AC again.

domyz

iTrader: (6)

First I don't know if you are aware of the three upper right tables and are related to initial steps position and not demand%. It would make things easier to tune, giving the system a baseline before adding the demand%. You cold values shouldn't be all the same, they should follow a curve. Maybe this is drifting your demand trims positive.

Also there should be more difference between intitial steps AC off and AC on. It should be closer than the stock steps difference. Again maybe this is drifting your demand% trims.

Finally I think you should start over from stock values and only tweak the initial steps position + stepper lookup.

Here are my current settings, I'm near a perfect idle in all situations (demand% tables are stock):

Edit: these tables are still on testing, and are not on target yet.
Edit 2: I found that it's best to leave the stepper table linear, so for a demand% value, all the steps will be the same. Non linear idle will be corrected by changing initial steps.

domyz

iTrader: (6)

^^ My new stepper lookup table looks like that because I found that it needs more steps from demand% on cold temps than on warmed up engine.

Raptord

iTrader: (10)

I just noticed the ISCV trim formulas for evoscan in the OP. I'll log those and see what's what.

Dynotech Tuning

iTrader: (12)

So is this correct?

"Desired ISCV Initial Step Position" + "% Demand" = target ISC Step position

"% Demand" is looked up in the IDLE STEEPER TABLE

"ISCV Demand trims" add or subtract a percentage to maintain the target idle.

What I am not sure of is where the "ISCV Demand Trim" value is calculated from, especially when its negative. Does it reference the IDLE STEPPER TABLE and use it as the +/- lookup?

What i mean is... is (-)10% removing the same ISC steps from the IDLE STEPPER TABLE as (+)10% would add?

-Jamie

domyz

iTrader: (6)

Top part seems right. It's all guessing here as we test things but nobody ended up with an official conclusion.
About the trims, it will need more field testing. I'd guess that negative or positive trims would adjust the %demand on the Y axis, so the stepper lookup value would be changed... So in your words, no 10% negative wouldn't be the same as 10% positive because the lookup table isn't linear.

I'm still trying to confirm things.

Dynotech Tuning

iTrader: (12)

I'm hoping to dig a bit deeper into it this week. My thinking is that the ISCV DEMAND TRIM is what is added or subtracted from the DEMAND% but I need to do some logging to be certain how they all work together. With MrFred stating a maximum of +/-16% of adjustment for ISCV DEMAND TRIM, in my IDLE STEPPER TABLE, 16% is roughly 40 steps so that seems like it could be plenty of range for trimming. The first 16% on the Y-axis is also linear and the steepest slope as well.

-Jamie

Dynotech Tuning

iTrader: (12)

Another question. Does anyone know if the ISCV DEMAND TRIM is trimming the ISC Steps under all conditions or only at operating temp idle?

-Jamie

domyz

iTrader: (6)

I'm working on this right now (temps near 0F here tonight) and I see the trims working to reach target idle on all coolant temp conditions. Proof is the Target idle RPM table is coolant temp dependant.
I'm stuck for now and I'm about to throw my old laptop into garbage. Christmas will be a new laptop for me I think hahaha!

domyz

iTrader: (6)

My startup is currently just under target idle, the trims keeps raising to raise demand%, but the maxed out stepper lookup won't go enough high. So steps won't move. I need to max the lookup table higher than what I have.
The stock lookup table had WAY too much effect on steps for high demand%.
I'll update.

Dynotech Tuning

iTrader: (12)

What is your initial ISCV step in the idle table and what are you logging for 'ISC steps', Demand%' and 'ISCV Demand trim' when the car is idling at operating temp with all accessories off?

domyz

iTrader: (6)

Full operating temp:
950rpm
48 steps
~18% Demand
5,8% Trims
Last one don't seem to work, I log MUT 08 but it doesn't change. Maybe it's the wrong adress for 94170715. The way I guess trims for now is that I look at the demand% changing when it's off the target idle.

Dynotech Tuning

iTrader: (12)

So it's showing 48 steps in evoscan or in your Desired ISCV idle table?

domyz

iTrader: (6)

48 steps logged. In fact my demand is 18% not 27% (I mixed things in my head). The logged steps aren't related to initial steps.