DFCO questions / definition in HP tuner

[eriktreves]

DFCO.JPG

what are these and how do they play with DFCO???

thanks in advance

[murfie]

Those are used for the rpm limiter. Nothing really to do with DFCO.

[eriktreves]

THanks... I think I may be getting closer... more from process of elimination unfortunately... I finally have some engine breaking but it seems like it kicks back to life (with an exhaust pop) and tries to drive away at 1200-1280 RPM...only if I tap the throttle though... so I either have to push in the clutch or apply brake. I was thinking about messing with Fuel Cut Ration vs Requestor ( idle speed control )?? Seems like I am closer ....

[murfie]

How did applying negative torque values to the positive RPM error in the idle PID control work?

My guess as all you have to work with is RPM error in decel with out a speed sensor.

idle PID.PNG

[eriktreves]

that test is the one I just loaded into the car.... will report back after I try that one. and THANK YOU....!!!!! awesome resource here!

[murfie]

Make sure your minimum correction is in the negatives. I think stock it was -41.

[eriktreves]

This ecu when I read it out of the box had 0's all the way down the line

[murfie]

Yeah the proportional table did, but the min correction you set to 4. I think it was at -41 stock. The proportional changes wont help if minimum is 4.

[eriktreves]

Gotcha... I had negative in there before with no effect , but with my P Gain with all zeros... then with the relationship you present I guess that's why!

[murfie]

You may need to increase your Enable RPM error to 1000 RPM. This way it goes into closed loop Idle control sooner. Right now it would need to get below 950 RPM to take advantage of the PID control. at 1000 it would start using closed loop at 1800 RPM to return to idle.

[eriktreves]

and of course it's raining today...lol... guess I will just try the idle recovery in the garage....

[eriktreves]

Small changes .. one at a time... changing the RPM error to 500 made a change in the right direction... idle recovery while not snappy... is definitely liveable ... now it needs to stop raining!

[eriktreves]

still freakin raining... geez....I would love to get this thing figured out and verified!!!

[eriktreves]

ok Murfie... finally did some playing around the other day.... I still have limited engine break and less than snappy throttle with a pretty good engine hang coming out of 1st only.....

I did notice that my idle set at 800 would never actually get there it stopped at about 860....

I played with the numbers up and back that we have discussed without huge "ah ha" moment... so I started to see if nothing else could I get the thing to idle at the speed I set in the RPM > Base IDLE RPM.

So I let the thing warm all the way up....

and I messed the ETC Predicted Throttle Angle vs. effective Area vs VAC..... I noticed that there was a "bump" or increase in the area around where the RPM it would seem to hang as well as where it idles.... so I removed about 20% in that area and now the IDLE RPM will hit the target that I set in BASE IDLE RPM.... Throttle seems nice as well and it does recover well in the free rev condition....

way too fricken cold to go for a drive... any thoughts about what I did? > I do have a TSP intake and stock TB... my BOV is closed at idle.

[eriktreves]

bump

[eriktreves]

well looks like the ETC predicted adjustment has FIXED my 1st gear hang....FINALLY!... also idle is nice and stable now for the most part... no ill effects in my cruise... and on the small down hill I have been using I am actually feeling some engine braking! I datalogged some and I need to make another adjustment one row over and I think that will bring it in... or at least I am hoping.... not sure why exactly this fixed it... maybe since I don't have VSS into the ECU, this is how ford determines the load.... not sure but looks like it might be a light at the end of the tunnel......