True Flex Fuel Tune

[K4fxd]

Brazil only. It's inconclusive as I didn't drive very far.

The dash read 14.0 AFR the long trims were running 35% and the shorts stabilized around zero. I did drive a mile or so and no wrench light.

I didn't want to get stuck flashing on the side of the road with traffic so I stopped the test and reflashed my normal tune.

The long terms turned on almost as fast as the shorts.
I wonder if it turns off the wrench light for LT's.

I timed the learn cycle with Brazil on and off, no difference that I can tell.
I also changed the flex update and saw no difference there either. It is scaled to seconds so the F150 setting of .01 should update faster than .1

I returned it to .01

I don't see any reason to use the Brazil switch but I also don't see any reason not to, as long as the rest of the flex parameters are on.

I would LOVE to see a read of a Brazilian mustang.

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[Rolls]

We have the Brazil strategies in the database afaik. If you can find a vin you could look up the as built n then find that strategyn in the strategy list.

 

[K4fxd]

I'm striking out. I cannot find a single window sticker or vin for any car in Brazil

 

[WildHorse]

ask this guy for the VIN
https://www.facebook.com/marketplac...wse_serp:4d3baf73-32aa-4475-8be9-9ac4e01ee99b

 

[K4fxd]

Facebook won't let me send him a message.

 

[WildHorse]

Facebook won't let me send him a message.

upper right corner where it says "message".

 

[K4fxd]

Big rectangle box that says message. I typed out a message in portugese and it greyed out the send button

 

[Rolls]

Look on online car sales. You can even google half the vin number and find sale listings to get them that way sometimes.

I've asked some people I know as well.

 

[K4fxd]

Look on online car sales.

Thats what I have been doing. Looking at dealers for a window sticker or like here in the states lots of dealers list the vin. But no luck.

 

[engineermike]

I'm working on an alternate "safer" idea right now. I need to make a transition to gas later this week to verify if it works. More on that later.

Ok, finally got a chance to test this. The idea was to set the ethanol learning to a maximum of 60%. Let everything fuel-related work the way Ford intended, except the timing. Add *all* of the additional timing between 59 and 60%. In this way, when switching from E85 to gasoline, the PCM only has to learn 1% ethanol in order to turn the additional timing back to safe gasoline numbers. I tested it and found that it learned the 1% after it consumed about 1/2 lb of fuel. If you recall from earlier, it takes about 1/2 lb of fuel for the new fuel to begin to reach the engine. Basically, as soon as the gasoline reached the engine, the timing switched to lower numbers even though it took another 1.5-2 lb for gasoline to fully purge the lines. I wouldn't call it foolproof, but you'd have to try pretty hard to blow it up when using this strategy to control fuel switching.

There are downsides to this, though. Technically, the E85 could be 51-59% ethanol in winter. If this is the case, then you may never get the additional timing because it won't learn to the needed 60%. The other downside is that if you get true E85 for a couple of tanks in a row, then the fuel trims could run as high as +14% because it can't learn past E60. It's not the end of the world, but I really like my composite fuel trims as close to 0 as possible. So far in typical situations I'm seeing 5-7%.

 

[K4fxd]

Technically, the E85 could be 51-59% ethanol in winter. If this is the case, then you may never get the additional timing because it won't learn to the needed 60%.

Do you have the knock learn off? It should add timing to your MBT.

The other downside is that if you get true E85 for a couple of tanks in a row, then the fuel trims could run as high as +14% because it can't learn past E60.

Most times the E85 around here is actually E75 so I would raise it to this.

 

[K4fxd]

What is the alcohol add table number in PCM. I want to ask if it can be added to a gen 2 through the custom OS feature.

 

[engineermike]

@K4fxd the tables in pcmtec are auf73806 and 73838. It would be cool if you can add that logic using customos.

 

[engineermike]

Do you have the knock learn off? It should add timing to your MBT.

The Gen3's generally don't use knock learning. I've tried for a couple of weeks to get it to work in my Whipple OS but not luck. No matter what I did with the parameters, the modifier wouldn't budge off 0.

 

[Rolls]

This is where using a flex sensor is going to be 100x better than the inferred ethanol. Run any mix your want. We can add in a purge delay as well so it lags the signal by the fuel consumption just like the oem system also.

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