I don't think we have any ethanol-free gasoline anymore in Finland. It's either 98E5 or 95E10 in all places except for the few that sell E85 too.Fred wrote:It only has ethanol in it in some places. In NZ for example one company sells fuel with ethanol in it, the rest do not. Around different parts of the USA the deal is the same, between zero alc and lots, but it's certainly not stable, which is the issue.preludelinux wrote:an ability to tune for pure gas ( which contains at least 10% ethanol and suppose to go up in a couple years )
The blends are like "up to 5%" for E5 and "up to 10%" for E10 and "up to 85%" for E85, so there is no reliable way to know exactly what you are buying. Some probably released a lot of water circulating in their fuel system too, when all the gas stations switched to E5/E10 from E0 in the middle of the winter in early 2011 (causing general E10 paranoia and urban legends regarding the fuel).
The flex fuel sensors on older flex fuel cars operate emits a frequency pulse between 50Hz and 150Hz depending on the ethanol content. 0% ethanol = 51Hz and 25% = 67Hz.If there was code for the flex fuel proper sensor, you could read a pot with it instead and adjust it that way, I guess.
However, the new flex fuel cars don't have the sensor anymore, because it was both unreliable (in terms of durability) and expensive.
The newer cars have an auto-tune feature, which triggers every time the fuel gauge shows a larger reading than it had the last time the engine was running (meaning the tank was filled up).
The auto-tune then runs for a while to create new fuel/ignition maps, probably by switching previous settings occasionally into one direction or the other and measuring the effects of the change.
However, a rough user-adjustable potentiometer dial would be better than nothing.
