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I don't understand the top row. What does it reference?
It appears to be a table that gets used during Idle and TR events
This is the description;
[ECM] 10092 - Spark Delta: This is the spark delta used during torque control events when commanded by the TR Command Spark Retard
Spark modifiers that use a ratio reference that table. It’s how something like the burble logic or the CSER works on gen 3 coyote. If you command a TR of 0.2 in the burble tables it’ll reference this table and whatever load it’s at to figure out how much timing to pull.
I have a gen 2.
It is idling in MP 15 at .30 air load 750 RPM calling for 33 degrees of spark. Actual spark is 12, would this equal engine load .3 at TR .93?
If so where or what causes the ECU to pick a reduction amount?
Thanks.
The column axis is torque ratio. If it uses spark to reduce torque, then desired torque/brake torque=torque ratio. It looks up the timing reduction on the table in question. It subtracts that reduction from mbt then commands that value.
Ok, I have been able to verify your explanation. Thank you. I assume this is something I don't want to mess with? or is it ok to use to add spark at say idle? or during a shift? I'd like it to idle with 14 to 16 degrees.
I have found that Tq module switch ECM 44770 turns this off. With this disabled it idles with 33 degrees of advance It is a lot snappier on the throttle but oscillates when coming back to idle speed. I'm assuming it is using fuel cut to control tq?
Am I on the right track in my thinking
The spark torque reduction S curve is a function of the physical characteristics of the engine. If you change the numbers then the calibration is no longer accurate. Many things in these tunes have ripple effects, so it might fix what you want it to fix, but cause 6 other problems. This is what I would call a band-aid fix.
Ford controls idle by holding the throttle [mostly] steady and using spark timing and a PID feedback loop to hold the speed at target. Spark timing works better than actuating the throttle because it responds faster than a throttle blade. But in order for spark timing to have enough influence, it has to be running well below MBT. If you're trying to control torque but are only a couple degrees below MBT, then it just doesn't respond to changes very much. So, in order to get the timing well below MBT, the throttle has to be opened more. So, they open the throttle more then the timing has to retard to get the speed down, then the timing has good control of it.
When you disabled the spark control of torque, then it runs more timing at idle as you've seen. But now it's likely falling back to throttle control, which doesn't work as well as you've noticed.
A better way to do it would be to make the throttle close more at idle by reducing torque request (less torque reserve, for instance). This will cut throttle back and it will be forced to run more spark timing. However, you will sacrifice stability.
You mention the throttle being a lot snappier. However, the spark timing should be put back immediately when the throttle is tipped in so the idle value shouldn't affect the response. There are a couple of other spark limiters that could be affecting the response.
My recommendation would be to put it back stock and then log a limited number of parameters on a very fast polling rate. Log timing, spark source, spark TR, pedal, throttle angle, rpm. Then determine what is limiting spark immediately upon tipin, and focus your efforts there. If it's not snappy enough on tipin, it's because Ford wanted it that way and ideally you should go after that. It could be something like tipin knock retard or TR ramp rate. If so, then you can adjust those.
I don't have "Spark TR" PID. Is this something I can have added by support?
Thanks for the explanation. Very helpful.
In my scanner it’s called “TR command spark retard”. You could also log “torque mgt advance”, which is the outcome of the calc.
K44 how did the tb angle respond with 33 degrees of timing compared to the normal 7 or 8 degrees?
Good stuff Mike.
Have also found the return to idle and idle in general is more stable with more TB angle. The opposite created cyclical idle blips when pushed to far. Very annoying.
I don't see those channels. Maybe its a gen3 thing?
That stinks. You’ll just have to use the spark source and torque source and go from there then.
It rode 4 degrees until I blipped the throttle, then it oscillated up to 10 and down to 3. So like Mike said it is using the throttle blade to control idle.Quote:
Originally Posted by Grim5.0
I don't have the channels either.
Spark source goes into torque control which I assume is the table above??