FuelPartThrottleEnrichment

[Frank]

How does this parameter work? What is EPP?


Thanks,
Frank

[Frank]

Anyone?

[Frank]

Bump...

[ShelGame]

That table is basically the time constant for the MAP averaging function. It really shouldn't need to be tuned. Though, it does seem to have a big effect on transient fuel...

[Frank]

And that is why I ask. I have been having problems with transient fuel. I have had it since I deviated from stock. I have a 3-bar and +20's with next to stock car. When I go to accelerate from a no throttle vacuum, it blips way lean before going to normal conditions. It sometimes stutters. I added some to the transientfuelfrom TPS, however it has not helped significantly. It is worse after a decent deceleration.

Ideas?

Thanks,
Frank

[ShelGame]

You could try to un-scale the table above. I haven't done the math yet to see how they developed the time constants. So, I'm not sure if they need to be scaled or not. I think in T-LM both axes are scaled (carryover from Geoff's code). But, I didn't scale either one in T-SMEC.

[Frank]

So what does EPP stand for?

[Frank]

Here is a graph of what I am looking at...

[ShelGame]

What's the MAP reading at the mis? I can't tell from the scales on your chart.

BTW, is that chart from LogWorks3? Nice...

[Frank]

Actually the chart is from Excel 2007. The MAP value is -8.1psi

[ShelGame]

Hmm, without checking, my guess is that the breakpoint between the idle adaptive cell and the vacuum adaptive cell is about right there. It might be that the breakpoint needs to change (lower).

[Frank]

I pulled my adaptive values and mapped them against the calibration...

 
Adaptive Idle Cell (12) = rich EC
 
2752  +---------+---------+---------+---------+---------+---------+
      | rich B3 | rich B5 | rich F3 | rich FF | rich FC | rich E8 |
1856  +---------+---------+---------+---------+---------+---------+
      | rich B3 | rich DA | lean 00 | lean 05 | lean 01 | rich E7 |
RPM 0 +---------+---------+---------+---------+---------+---------+
  MAP 0       -10.6     -8.3      -6.1      -3.5      -0.9       1.1

You might be on to something. I am sure my figure of -8.1 may not be very accurate. So what do the values in the cells actually tell me? In the case of "rich B5", does it tell me that my actual fuel curves are too rich?

[Frank]

How does this guy work? AutocalO2CtrlDeadbandLimitForUpdatingCells

[ShelGame]

I pulled my adaptive values and mapped them against the calibration...

 
Adaptive Idle Cell (12) = rich EC
 
2752  +---------+---------+---------+---------+---------+---------+
      | rich B3 | rich B5 | rich F3 | rich FF | rich FC | rich E8 |
1856  +---------+---------+---------+---------+---------+---------+
      | rich B3 | rich DA | lean 00 | lean 05 | lean 01 | rich E7 |
RPM 0 +---------+---------+---------+---------+---------+---------+
  MAP 0       -10.6     -8.3      -6.1      -3.5      -0.9       1.1

You might be on to something. I am sure my figure of -8.1 may not be very accurate. So what do the values in the cells actually tell me? In the case of "rich B5", does it tell me that my actual fuel curves are too rich?

I think so - that's a signed number, so B5 is actually -4A; that's a pretty big adjustment. At ~8.3 psi, you switch to the next cell which is only F3 (-0C) rich. That's a really big change from cell to cell.

What I was thinking actually, is that the -8.3 psi cell boundary might need to be changed to -8.0 or even -7.9 to keep you in the low vac cell longer. But, it certainly looks like you're very rich in the low vac cells.

[Frank]

I think so - that's a signed number, so B5 is actually -4A; that's a pretty big adjustment. At ~8.3 psi, you switch to the next cell which is only F3 (-0C) rich. That's a really big change from cell to cell.

What I was thinking actually, is that the -8.3 psi cell boundary might need to be changed to -8.0 or even -7.9 to keep you in the low vac cell longer. But, it certainly looks like you're very rich in the low vac cells.

Interesting. So maybe first, I should go through my calibration and make my FuelPartThrottle closer to my A/F settings in attempt to force the adaptives to operate closer to zero. Once I see how that is played out, then maybe I will adjust the cell boundary to match the driving styles.

I imagine that as we change the curves, boost, turbos, etc, on our cars, the car is going to load and accelerate differently and the adaptive cell boundaries are going to need to be changed more then we are used too.

Oh and in regards to the thread title, that table should be under the Load Enrichments section, not transients. I was looking through the Chrysler docs and noticed that.

Thanks for the help,
Frank

[ShelGame]

Interesting. So maybe first, I should go through my calibration and make my FuelPartThrottle closer to my A/F settings in attempt to force the adaptives to operate closer to zero. Once I see how that is played out, then maybe I will adjust the cell boundary to match the driving styles.

I imagine that as we change the curves, boost, turbos, etc, on our cars, the car is going to load and accelerate differently and the adaptive cell boundaries are going to need to be changed more then we are used too.

Oh and in regards to the thread title, that table should be under the Load Enrichments section, not transients. I was looking through the Chrysler docs and noticed that.

Thanks for the help,
Frank

I think part of the problem, too, is that the actualy MAP values change slightly when we re-scale for a 3-bar MAP due to loss of resolution. So, if the MAP boundary was 8.3 with the 2-bar MAP, it will be shifted slightly when we change to 3-bar.

[Frank]

So burned the new calibration and will pop it in come morning. I made all of the fuel vacuum points back to stock. I don't know why I changed them so long ago but I have copied them over and over for a while now. I also made the map boundary -8.3 to -7.8 and -6.1 to -5.9. I also put the MP VE in v8 to somewhere between that and the stock that is in v6.

So I use a chip extender. How quickly do you think the adaptive will fix themselves since I won't be pulling the power from it? It would be cool to implement code that if engine is not running and in the "give codes mode" and you do 5 WOT triggers, that it writes all 0h00 into the adaptives in memory.