Quote from: ecoboostsho on December 11, 2015, 09:23:25 AM
I'm 95% confident (hey I could be wrong!) that there isn't an Octane sensor. Perhaps someone who really knows can chime in. From everything I've seen LOR is "inferred" based on the engine's ability at different throttle positions to not knock. If it can advance timing and not see knock at various load levels then it "assumes" that you must be running a higher octane fuel and it will advance the LOR so you get to run more timing. If it sees too much knock then again the ECU assumes you've put in some craptastic gas and moves the LOR in the appropriate direction.
If that is how it works then ACES would HAVE to prevent knock to enhance LOR since that is the only way it can affect it. There might be other variables involved with LOR though but again I don't think an actual Octane sensor enters in to the picture. That said I have no idea what ACES claims to do so I can't comment.
It would not surprise me if the car paid particular attention to knock and adjusting the LOR value right after you fill up. That would trigger the algorithm in the ECU since you obviously just put new gas in.
I am basing most of observations off of this article:
http://www.cobbtuning.com/ford-ecoboost-and-the-octane-adjust-ratio-monitor/
Im pretty sure you are right about lack of actual octane sensor. And I know we splitting hairs here, but you can't put the cart before the horse. The LOR has to be seen BEFORE timing can be adjusted. A crappy LOR and no knock present nets more timing. But hi number of knocks and a superior LOR nets less timing. If ALL of the "protective" features built into the ECU are calculations, inferred, or theoretical any glitch in the primary sensor (there would have to be at least 1 physical sensor) used for calculation, the ECU fail to safe mode and NOT run. Theoretically.
I also don't believe throttle position directly affects ANY performance parameter. That is a calibration and variable used for fuel delivery/demand. (I guess that does affect performance huh lol). 100% throttle and inadequate fuel delivery or rail pressure per flow curve nets engine cutting power. Theoretically!
I have seen this on my GMC when throttle position and throttle body doesn't calibrate properly at startup. So it disables the drive by wire and truck becomes useless until reset.
All of the sensors and calibrations are part of a HUGE formula to determine and dictate load and demand.