EcuEdit questions... what do these tables do?

[thejean]

1. RPM vs Throttle - #11 - 282D4
2. RPM vs Smoothed Map Manual - #15 - 2A691
3. Overrun Feul Cut-Off Delay - #05 - 29857
4. Idle Air Flow Map - Coolant Temp Based - #91 - 280F8
5. Idle Engine Load Map - Coolant Temp Based - #91 - 2811E
6. Throttle Angle - Into Idle - #00 - 2829E
7. Throttle Angle - Out of Idle - #00 - 282A3

I could take a guess but would like opinions from those in the know.

Thanks, JC

[Freon]

Post your ROM and your XML. Can't tell you what I can't see.

[Freon]

1. RPM vs Throttle - #11 - 282D4
2. RPM vs Smoothed Map Manual - #15 - 2A691
Don't know, I'd have to see your ROM and XML to make a guess.

3. Overrun Feul Cut-Off Delay - #05 - 29857
I think this has something to do with injector cut when engine braking. Not sure.

4. Idle Air Flow Map - Coolant Temp Based - #91 - 280F8
I believe this map is used to target a certain airflow. This is used in conjunction with the other idle rpm maps. Bumping this up might help with big injectors. Not 100% sure. I think this is a "target load" map.

5. Idle Engine Load Map - Coolant Temp Based - #91 - 2811E
Same as above, but a compensation based on coolant temp. It will try to run a higher load at low coolant temp to help the car warm up faster.

6. Throttle Angle - Into Idle - #00 - 2829E
7. Throttle Angle - Out of Idle - #00 - 282A3
Throttle angles before the idle control code takes over, I assume. I.e. under 2% throttle or whatever, the car uses its idle control algorithms rather than the closed loop cruise or open loop code. Probably shouldn't be touched.

[thejean]

Post your ROM and your XML. Can't tell you what I can't see.

Here you go:

[thejean]

Freon, do you think any of these tables could be manipulated to make the throttle plate stay slightly open during 0% throttle?

[Freon]

Not sure how that would be physically possible on a drive-by-cable car. You could perhaps trick the ECU to keep your idle control valve open, but not the actual throttle since that is a physical connection. I wouldn't know how. I doubt it is easily possible without screwing up your idle horribly. The amount of air that can pass even fully open is probably negligible at higher rpm as well if you're trying to figure out some sort of antilag.

After looking at the ROM, I'm more certain the explanations above are correct.

The overrun fuel I'm pretty darn sure is correct.

RPM vs. Throttle #11, I wonder if that has something to do with the crankcase pressure solenoid system. That smoothed map, I really don't know.

[thejean]

I definitely think you're right regarding the overrun fuel cut-off.

However, idle is controlled by the IAC so these tables probably control the IAC valve?

If the throttle plate is manually cracked open a bit more using the adjustment screw but no changes are made to the idle control logic, the car should still idle no problem, right? I mean, the car should only idle at the speed fuel is injected, correct?

[thejean]

What do you "think" the units in the overrun fuel cutoff delay table are? Milliseconds, seconds? At a MAP of 1.0 MPa, the value is 49 and at a MAP of 1.5 MPa, the value is 0. Sooo, say we decelerate all of a sudden... RPMs drop, MAP drops, and value goes from 0 to 49. Given its a "delay", I would think its a time value but I can't be certain.

EDIT: Looking at it some more, I think the values in this table may be ignition timing.

[thejean]

How about these tables?

[thejean]

How about this map? What does CPC mean?

[Freon]

No clue. I think that CPC map is the duty cycle on the crankcase vent solenoid.

[Tea cups]

CPC = Canister Purge Control

[thejean]

What do you guys make of these tables?



Strangely, the scaling factors for the timing in these tables is different than that of the main ign table...

For example, the scaling map for ign accel comp is [value]/2.8444-45

Meanwhile, the Main ign map is [value]/2.8444-20

And for the ign boost error compensations, they don't subtract anything.

Any thoughts on why this would be?

[thejean]

And what do you make of these?

They seem to be engine acceleration tables of some sort... but the ECU values don't seem to make any sense to me. These are the raw ECU values by the way.