Flex Fuel Control

[efloth]

I am considering implementing Flex Fuel control for A1C. The tasks required are listed below. Let me know if you have any input or ideas.

1. Move AFR normalizing parameter 0x50AA to KAM address space (KAMAFR).
2. Patch fueling code to read from new KAMAFR address for normalizing.
3. Update KAMAFR based on rolling average of Lambse at idle when ECT exceeds 170F (or is there a better rpm to allow updates, or all time rolling average?)
4. Implement multiplier of CrankPW based on CRANKPW = FN1350 * (14.64 / KAMAFR) (This is probably too simplistic)
5. Implement multiplier of FN2225 simaliarly (Will need help with this one)
6. Missing anything?

[jsa]

3. I reckon any time it's in closed loop. If you fill the tank with some different soup, how long will it need to idle to adjust??

[efloth]

It should not take long once up to temp. Probably best to increase KAMAFR 5% at a time over 10-20 sample average.

4. Rethinking the formula for CrankPW, this should be more accurate. CRANKPW = FN1350 * ((((14.64 / KAMAFR) -1) /2 ) + 1)

[efloth]

It appears that the 106 KAM addresses are from [74d] to [7b7] based on this routine. Thinking of using [7b8] for KAMAFR

Code: Select all

a10d: ad,6a,30            ldzbw R30,6a           wR30 = 6a;
a110: 01,38               clrw  R38              R38 = 0;
a112: b3,fe,3c,3a         ldb   R3a,[Rfe+3c]     R3a = [bc92];
a116: 38,3a,1c            jb    B0,R3a,a135      if (B0_R3a = 0)  {
a119: af,31,4d,07,3a      ldzbw R3a,[R30+74d]    wR3a = [R30+74d];
a11e: 64,3a,38            ad2w  R38,R3a          R38 += R3a;
a121: e0,30,f5            djnz  R30,a119         R30--;
                                                 if (R30 != 0) goto a119;

[decipha]

why would you do that ?

what is 7b8 for?

[efloth]

to save ethanol percentage between restarts

[decipha]

i understand what u want to use it for but what is it currently?

dont forget the ram checksum too

[efloth]

Only the first 106 Kam addresses are used and checksum’ed. based on input from wwhite and jsa the remaining addresses are available for use

[sailorbob]

There are KAM addresses used below 0x074D so you may find addresses above 0x07B7 are used too.

[red5.0fogger]

won't it need a flex fuel sensor to avoid undo learning time? I know not of coding however, lol.