Has anybody seen this kind of spastic ETC action and been able to correct it?
ETC spaz.jpg
This is a 2017 with a Procharger.
You can see this fueling is on target, no IPC TQ errors, no real ETC angle error. It just suddenly starts getting very erratic with ETC angle and spark advance, then it goes away.
Unless there is some shift between channels, it actually looks like spark starts the war and ETC is chasing.
ETC-spaz2.jpg
This screenshot shows what I mean about the spark starting it. But, I still don't understand why.
Despite smooth pedal input, smooth ETC TQ, smooth scheduled TQ, no driver demand limits, no change to spark source, no major changes to cam position... it is rapidly dropping spark advance by over 10*. This obviously causes a dip in brake TQ. When the spark advance does this in rapid succession, the ETC starts to chase after it.
Looks to me like a IMRC problem. But not really enough info given to say.
Speculation:
19 seconds in the IMRC go from partially open to shut.
20.5 seconds in they go from shut to partially open.
Then your spark and ETC issue starts. Kinda a blend of what are normally open and closed mapped points. Not a well defined condition, as it shouldn't be seen for long periods of time.
Last edited by murfie; 10-06-2022 at 04:00 AM.
Originally Posted by murfie
Thanks for the suggestion Murfie.
IMRC should be fully disabled. Did I miss something?
IMRC.jpg
You have too many mapped points with the same angles. You should run either the IMRC open or the closed tables to prevent this. You have timing blending between 4 or 5 mapped points and that's why your spark is sporadic. That table doesn't disable anything. That table is actually an Open/Close. It doesn't matter if you run the original Open or CLosed mapped points, you'll set them to 1.0 in that table.
Awesome, thank you.
Which MP's would you disable with IMRC removed and a centri blower, 14-25?
Mapped points 1, 4, and 20 are unique to their calibrated IMRC position. Which ever set you choose to disable after removing the IMRC, their isn't a quick and easy route around having to recalibrate your points a little bit.
looking at the IMRC load for opening/ closing tables for the fuel economy and drivability modes. Distance 4(MP4) or distance 8(MP20), and the transition around 3500-4000RPM. These are spots in the calibration you need to review either route you choose to take. 5,6,7 blend with 17, 18,19 in IMRC transitions closed to open and open to closed.
So eliminating all that if you want to keep it simple, its do you want to use 0,2,3,5,6,7,8,9,10,12 or 14,15,16,17,18,19,21,22,23,25. Plot those angles out, build your snap to points and lines for the mode arrays, and set the distance tables up to 10 around those 10, with out the IMRC transitions.
When you are tring to make it simple like the 11-14 non IMRC cars, but have midlock intake phasers (mainly added for better cold start purposes).
This is what you are aiming for:
11-14 vs 15-17 midlock phasers.jpg
Last edited by murfie; 10-08-2022 at 04:51 AM.
Thanks Murfie and Thatwhite5.0, fully getting rid of one "set" of MPs and working to re-blend has made a very big improvement!
MBT spark values between those two "sets" are very similar. If you follow the logic I shared on how I manipulate my borderline table that I shared in my stock 2019 GT thread, you should end up at very similar borderline values using either set.
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