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This is a GMPP LS376/480 controller (E67). The cam, heads, and intake have been upgraded since the the original LS376/480 went in the car (a Miata).
I'm trying to get the DFCO to work. This is mostly a street car, so I want the best mileage out of it I can get.
The area in the screenshot under the cursor is about 43 seconds into the log file. If you look at the attached tune, I believe I've satisfied the ECT, cyl air, rpm, and speed requirements to invoke DFCO, but it's not happening.
The TPS requirements for DFCO are between "0-200%" in the table in the tune file. I'm not sure what sensor that 0-200% applies to, since there are many channels that log various representations of TPS. I could start blindly raising the table values for DFCO TPS enable in the tune, but if somebody knows exactly what channel I should be logging, please speak up now.
Your current TPS Enable settings are too low, and you will never enter DFCO . Requirements are ( [ECM] 12250 - DFCO Enable TPS vs. RPM: Throttle position must be below this table value.)
As an example you can use similar values as the screen capture
Did DCFO work before the engine mods?
Asking because I tuned one of these ECU's and don't recall DCFO working.
Looking at your tune and the logs, I think FrankieD is correct. You never get to the limits in your tune file to activate.
With quite different airflow now that you modded the engine, the TPS may behave differently.
I can't say what TPS it's looking for. The typical actual TPS on a DBW setup rarely gets below 10%. So not sure if Relative TPS is the correct thing to log. But it still doesn't drop below the values in your stock table.
Ron
Last edited by RonSSNova; Dec 30, 2020 at 02:47 PM.
Thanks, Ron and FrankieD. Those DFCO TPS thresholds were from the original LS376/480 tune. I've modified them a bit since, trying to get it to work.
I don't recall if DFCO ever worked with the engine as delivered from GMPP with the hotcam in it. I'm working harder on the tuning than I ever have, so I'm getting deeper into stuff.
Am about to post current status.
Last edited by grubinski; Dec 30, 2020 at 04:30 PM.
So here you go. This is a capture of the log, and a screenshot of my DFCO set up.
I'm in 6th gear, 66 mph, so that should enable DFCO. I'm at .088 cyl air at 1833 rpm, so that should enable DFCO. I'm at 2% relative throttle, and 13.7% SAE throttle, so either one of those is less than the 90% (!!!!!!) I set the TPS threshold to in order to try and take TPS entirely out of the picture. You can see I have ZERO delay for fuel cut.
Still no DFCO. Does anybody know if the GMPP LS376/480 controller even supports it, or did they turn it off for the aftermarket (GMPP) controllers?
YES, the temperature conditions and rpm conditions are also met.
Do I need to set minimum injector pulsewidth to zero or something???
Thanks,
Mike
Last edited by grubinski; Dec 30, 2020 at 05:11 PM.
On this OS, it wants cylinder air to be below a certain value. That's strongly related to MAP. The cylinder air requirements are met when I think it should be going into DFCO and isn't.
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DFCO not Engaging 
