'04 Express P59 Flex fuel options

[nsogiba]

Motor is a 2004 Express 6.0/80E in a 2011 Crown Vic. Got the swap done, turbo kit is ready to be installed, just wondering about fueling as we go forward. I currently have the car roughly tuned on 93 pump gas, but when the turbo is installed I'm wondering if it's worth it to just go to straight E85 for the safety factor. Flex Fuel doesn't seem to be an option since I only have the 2 bar / 3 bar option available for my PCM. Still need to check the hardware #/OS, it's the factory PCM out of a 2004 Express van.

I'm wondering if I should just fill it up with E85 and tune the VE now, so that when I'm done installing the turbo kit I can just work on the boost fueling (PE/BE) and enjoy it. I've never messed with E85 so I'm not familiar with the general ignition and AFR targets. What's a good starting point for 10-14 lbs on E85 for AFR scale on an AEM UEGO, and what can timing start at? I'd just go and read plugs from there to see how it's liking it. This is purely a street car so I'm not looking to wring every ounce out of it, just want a safe fun setup that I can hammer on all the time.

Is my current PCM (P59) and OS compatible with Flex Fuel? Do I need a segment swap or an entirely different PCM altogether?

Here's what my '04 Express P59 shows currently - already did the OS swap to a 3 bar.



Looks like Flex Fuel is already present in the tune, just need to enable it and tune VE/timing?

Do I just say screw it and tune it using the normal VE table and straight E85 all the time? Will the variation in alcohol content with different blends and times of the year cause enough of a difference to affect the tune (cruise/WOT)?

[5FDP]

You need to install a flex fuel sensor and wire it into the computer if you want to use it properly.

[nsogiba]

You need to install a flex fuel sensor and wire it into the computer if you want to use it properly.

Of course, I get that. I'm just wondering if my native file has the flex compatibility, or if I need to get a file (and license it) that originally came with flex.

[5FDP]

I think it needs the second drop down box that says Fuel sensor fitted or no fitted for it to be a true flex fuel file.

I don't see it on yours.

[kevin87turbot]

Your file isn't going to work in a flex fuel application. You'll have to chose either gas or E85. There are 2004 files that will work with flex fuel.

Here's a 2004 Tahoe flex fuel cal that I segment swapped to a 4L80E transmission.

Is yours a DBC throttle body? If so, this can work for you. It has a 2 bar MAP Sensor option too.
2004tahoe53Lwith4L80ESegmentand DBC TB.hpt

[nsogiba]

Thanks for the file. I'm not able to open it, it's saying unsupported or newer hardware detected. Might have to update my HPT software.

Anyone have a 3 bar version of that file? Mine is a DBC TB.

[TowinDaLine]

Thanks for the file. I'm not able to open it, it's saying unsupported or newer hardware detected. Might have to update my HPT software.

Anyone have a 3 bar version of that file? Mine is a DBC TB.

Can't help with the 3 bar, but as far as the sw version -- you should be able to d/l the 4.x beta, install it on your machine alongside of the 3.x version if you want, and then use 4.x for evaluating others' tunes. You can also open your own 3.x files as 'compares' in 4.x, without hurting them (and never a penalty for making a separate copy, of course, except for the HDD space.)

I'm running both versions on the same Win 10 partition / login, with no ill effects.

Note that the v. 4 software has an auto-updater (or, at least, an automatic version checker), so if you're not wanting to be potentially interrupted with an ECU write, it's best to disable your Wi-fi (and anti-virus) before doing a write with 4.x It's also good practice to do that, even with a 3.x write (I keep a reminder pinned at the top of my logfile notes).


One last thing... I'm also in the middle of adding the flex fuel composition sensor, and wiring it into my own P59 (I have an '03, also). Already upgraded the fuel pump, and have 50# OEM flex injectors ready to add. But seeing @kevin87turbot and @5FDP's comments about "really being able to add flex" via the ECU gives me pause, now. (OP: If you need GM part #s for the composition sensor & the injectors, let me know)

[kevin87turbot]

Can't help with the 3 bar, but as far as the sw version -- you should be able to d/l the 4.x beta, install it on your machine alongside of the 3.x version if you want, and then use 4.x for evaluating others' tunes. You can also open your own 3.x files as 'compares' in 4.x, without hurting them (and never a penalty for making a separate copy, of course, except for the HDD space.)

I'm running both versions on the same Win 10 partition / login, with no ill effects.

Note that the v. 4 software has an auto-updater (or, at least, an automatic version checker), so if you're not wanting to be potentially interrupted with an ECU write, it's best to disable your Wi-fi (and anti-virus) before doing a write with 4.x It's also good practice to do that, even with a 3.x write (I keep a reminder pinned at the top of my logfile notes).


One last thing... I'm also in the middle of adding the flex fuel composition sensor, and wiring it into my own P59 (I have an '03, also). Already upgraded the fuel pump, and have 50# OEM flex injectors ready to add. But seeing @kevin87turbot and @5FDP's comments about "really being able to add flex" via the ECU gives me pause, now. (OP: If you need GM part #s for the composition sensor & the injectors, let me know)

Towindaline, what version OS are you running? I'm sure that I have a 2003 Cal file that has flex enabled.

[TowinDaLine]

Towindaline, what version OS are you running? I'm sure that I have a 2003 Cal file that has flex enabled.

(OP: Apologies for hijacking the thread; that wasn't my intent)


12579405. I do have the toggle for FF, but don't see the 'Fuel sensor fitted' toggle that 5FDP mentioned, FWIW

Also, if I activate the FF toggle, I don't see that 'fitted / not fitted' toggle appear.

Screencap below of what I have, showing the OS and FF info.

No need to send a cal file just yet, tho, as I've reverted back to stock for the time being while I work on some other things. But I'll take you up on a raincheck, if available. Finally, mine is a DBW, not cable. I'll start a new thread (or update my old one) when I'm ready to move forward - and *thanks*