Running flex fuel bin full time now.
If you're going to run it, it's at your own risk, and I'd suggest asking questions.

Anybody interested in running this respond to the thread and I’ll get you files. When I’m 100% done I’ll release a full bin and xdf to match.
I've got this all worked out, I need to put code in it's final place and setup the xdf and patch to implement, Then I'll need testers willing to give it a try. I don't have injectors to run E85 so I can't test myself.
Here's what the test bin will be:
AXXD ONLY, if you can't run this I'm sorry. It's all I work in.
Tables:
E85 Blend Ratio. This will be controlled by a tune (at first). 0% - 100% E85. Set it to your mix and go.
Injector Flow E85 Table. You'll enter in the injector flow required for E85 blend %. 0-100% = full E85 injector flow
Crank Fuel vs ECT E85. This is where you enter values needed for the table on 100% E85. (blended by ECU based off Manual blend ratio entered.)
Main Spark timing E85 and Extended Spark Timing E85. These are to have Full E85 timing values. (blended by ECU based of Manual blend ratio entered.)
VE E85 and VE Upper E85. These are to have Full E85 timing values. (blended by ECU based of Manual blend ratio entered.)

That's it. This thread will be for the development of this specific Patch from my $8D-T bin linked in my signature.



Edit: I just tested the code for On the Fly Flex Fuel Ratio changes. This will allow you to fill up, set what blend you believe is correct and go. All without having to burn a prom. It's not super elegant, but it works perfectly.
I'm working on the blending of 3d Tables Now. Then 2d, then the easy stuff.

Edit: I just finalized 3d table blending. WORKs beautifully. Next 2d and Injector scaling tables. Then as I said before it's finalizing addresses and code placement and it'll be done. But the great news is that the blending tests are perfect proving the entire project works.

Edit: I just tested 2D blending; WORKS. I just tested Injector lookup; WORKS.

Edit: Finished up Cranking PW, Injector flow, and both timing tables. Going to make a test bin to make sure it's implemented correctly cutting into the OEM code now. After that, I'll inject the VE tables too.

 

**********THIS IS A DEVELOPMENT RELEASE************
Not the finished product. SCAN AND WATCH YOUR TIMING AND FUEL! I am not responsible for damage. USE AT YOUR OWN RISK!!!




For now VE is not included, just the tables in images below.

Read every single table explanation and the readme.

Again, failure to follow directions will cause issue and I'm not responsible for it. This is a Developmental test release. It should work, but you need to scan timing and fuel to make sure.
xdf pulled.

 

To change fuel blend on the fly, with car off hold gas pedal down for your set time limit.
youll see the cel light up. You’re now in full gasoline blend. Release and Press pedal for 10% more blend. Ten presses is 100% full e85.
turn on the car.
done.

The other way to change your E85 blend is full manual mode. Set the check box and your blend and burn the prom.

The third option is a virtual ethanol sensor.
setting to this works just like the on the fly setting except when you turn the car on it reads the fuel response and adjusts the blend. So if your pump that’s supposed to be e85 is only e50, the car will adapt.
once you start to drive learning is cancelled.

 

 

Later I will implement a change to DriveMode Mode selection, add in a Virtual Sensor, and VE tables.

 

Although I personally don't have use for a flex fuel bin, I do want to chime in here and acknowledge the work you're doing. People dabbling in the code on these old ECM's is extremely rare these days, and you're helping to keep the hobby going.

Definitely appreciated!!!!

 

I don't really either. I can have a winter blend/weather tune and a summer blend/weather tune without swapping chips.
I can have an 87 tune and a mix of 30% E85/70% 91 octane on the same chip.
I can have an 87 and a 91 on the same.
There are certainly other uses beyond ethanol.

 

My fuel pump quit on me so the car is parked until I get one.

 

If anybody has a specific scaling for an ethanol sensor I can design the code to use it.

I setup the code to hold the gas pedal for a user defined time limit to prevent changing the blend ratio without purpose. needs a quick test before I release the update. Not that anybody else is running this yet.

Now I’ve setup the ethanol sensing code. No sensor needed. Tell the car to learn, it does. Tells you when it’s learning and when it’s done learning. Then you drive away with the proper settings.

no computer needed. No extra crap needed. All in one.

 

Edited the above posts to current implementation.
I can supply a bin and xdf to anybody wanting to test.

EDIT: No need for any testing really. Fully tested except cranking table. <--- People have downloaded the bin up top. Hope you don't plan on running it without asking questions as I said.

Running Flex Fuel Bin full time.

It’s really cool putting in a new high timing table and being able to blend into it without having to do multiple burns checking.

im able to do valet, 87,91 and e85 tunes all on the same single chip. I need to do this to my other cars now…

 

Now Includes indepth MAT adjustment.


As I said before, I'd advise asking questions before running this code.
Still no virtual sensor yet and no VE blending yet either. Running this full time. and everything works as designed. Haven't found any bugs yet.

 

I will be updating the bin file as soon as I'm done testing this. First gear and overdrive gear specific timing tables.
Flex fuel blends away from these tables just like the main spark table. So 100% e85 does not use them at all, 50% e85 blends them halfway between, etc.

Edit: tested. No more 5th gear knock. All set.

 

Although I probably can't use this, I will say I'm grateful guys like you are still active on this board who know the code....

 

Ditto to ULTM8Z, always love readin through updates on your coding adventures. I do have an interest in getting E85 working on my car at some point, but a bit further down the line... figure I'd need a new pump and probably injectors before I start thinking about E85. Would the fuel tables be that tricky to transfer over to $88? Not sure what differences there are between pinouts on $8D and $88 '7730s (if any), but I'm hoping the wiring side of my ECU could at least stay untouched. I figure the actual code itself is different in ways I do not comprehend at this time, but I don't see why it wouldn't be possible, given the hardware itself should be the same... in any case, thank you so much for all that you do for these old ECUs, it's really cool to see just how capable they are in the right hands

 

It is not possible to simply “copy paste” this work into any other mask.

Transferring this to would require somebody to port ONLY the ideas and rewrite the $88 code themselves. If its even possible (I have no idea) it woild take so many hours of work the labor charge would be $thousands.

I work in $8D and more specifically AXXC/AXXD only. I have no clue what the others even look like.

I could make a basic version of flex fuel in any mask, but have no reason to as I don’t own one.