Flex tune. Can someone look and see if I missed anything?

[K44]

Thanks

Car is my 2017 GT

[nicks1031]

Looks like you didn't populate one of the most important tables, ECM 21320 - Flex Fuel Ethanol % vs. AFR.

[Mustang]

I'm trying to understand this e85 stuff also. I looked at several of the F150 tunes on the repository and it looks like all of them have 9.0 AFR at 100% (Multiple rows say the exact same thing) and then a single last row of 14.6 AFR at 0%. I see stuff like that on other tables where it seems like the row/column headings are exactly the same and the values are exactly the same as well. I increased the decimal points as well, but they look to be exactly the same. Is there a reason why some are like that?

[LastPlace]

Thanks

Car is my 2017 GT

Try this

E85 FLEX FUEL - try this.hpt

[K44]

Thank you.

Before I load this, do you see anything else I may have missed or need to modify?

[LastPlace]

As far as flex fuel goes I think I got you squared away

[K44]

lastplace,

Thank you.

I see you modified my tune.

Thanks again

[LastPlace]

I surely did, Now you just need to get your spark tables dialed in

[K44]

I studied your changes and I think I figured out why you did what you did, except for the fueling changes to non FFV tables. IE cold start and I think a few others.

Can I ask why?

On the bright side I was chasing a slight stumble at slow speeds when on and off the throttle, that is gone. Thank you very much!!.

What parameters should I log when switching to E85? I am thinking about slowly working my way to a full tank. I would start with 5 gallons to a full tank and add a few gallons as the tank empties.

I assume I should watch commanded lambda vs measured. Anything else I should watch?

[LastPlace]

Compare it to an F150 and you’ll have your answer

Don’t get caught up on the inferred alcohol content is not that accurate just remember you can run the same spark at E60 as you can at e85

I’m going to guess that you don’t need to go over 31 degrees of timing

[blackbolt22]

I looked at several of the F150 tunes on the repository and it looks like all of them have 9.0 AFR at 100% (Multiple rows say the exact same thing) and then a single last row of 14.6 AFR at 0%. I see stuff like that on other tables where it seems like the row/column headings are exactly the same and the values are exactly the same as well. I increased the decimal points as well, but they look to be exactly the same. Is there a reason why some are like that?

In many tables, the PCM does linear interpolation to calculate the correct values in between defined points. In this case 9.0=100% and 14.6=0%, so as long as the minimum and maximum values are present, it doesn't matter if the table is fully populated or not, the PCM will have the data it needs.

Personally, I like to fill tables out to have more visibility but again to the PCM, it's the same thing.

EthanolStoich.PNG