Flex Fuel alternatives

[NoGuru]

I am looking into a Flex Fuel alternative to the Motive setup.

Quick summery on my issue with the Motive FF. I had it since it came out and it worked great for almost two years. Last fall just before I put the car away I was having issues and Motive was working with me on resolving them. Every component of the FF system was replaced and Motive even made a custom Wiring harness but could not get my FF working again. They have given me the best support I could ask for and I still think they make a great product. It just does not work on my car anymore.

That said, is there any other way to run Flex Fuel or are they the only ones who make it for the N54?

I think BMS has some sort of FF built into there JB4 but I don't know if it just changes boost target or what?

 

[GreyNBlueE92]

Can't you use any 5v output ethanol sensor as long as the scaling matches the sensor in the tune?

 

[typedRew]

afaik fuelit! has a kit that goes straight to the jb4, it eliminates the dme from the equation

@Terry@BMS can clarify hopefully

 

[Jake@MHD]

Can't you use any 5v output ethanol sensor as long as the scaling matches the sensor in the tune?

Yes. The ethanol sensor remains the same (Conti), the ECA would differ. The voltage -> E% table will need to be updated accordingly. Take care with what voltage the new ECA you choose outputs for error conditions.

 

[Cruizinmax]

It would seem pertinent to find out if your motiv ECA is putting out the correct voltage to E% or if the DME is interpreting it incorrectly before attempting to move to another flex fuel setup. If the flex fuel box is outputting the correct voltage switching to another ECA may yield the same problem you are currently having.

I'm not sure that JB4 has an option for a dedicated 0-5v input that would work for flex fuel. The only options I'm aware of are JB4 utilizing the DTML input (like the Motiv setup) and a custom BEF or their "virtual" flex fuel which doesn't use the E sensor at all.

 

[NoGuru]

afaik fuelit! has a kit that goes straight to the jb4, it eliminates the dme from the equation

@Terry@BMS can clarify hopefully

This is what I was wondering.

Again, I have changed out the FF module, wire loom, and sensor. The the entire system has been swapped and Motive cannot figure out what is wrong so my only options are to move to another system.

 

[GreyNBlueE92]

Does your evap show readiness if you're on a non flex tune?

Maybe the dme somehow got too much voltage and fried the input... Idk

 

[NoGuru]

Does your evap show readiness if you're on a non flex tune?

Maybe the dme somehow got too much voltage and fried the input... Idk

Good question! I don't know, I only have a FF tune as my tuner (BQ) was sick with Covid for a while and I have not received another tune yet. I am on aftermarket Turbos with lots of mods but I guess I could try and standard MHD tune.

How would I check for evap readiness? Just read codes right?

 

[GreyNBlueE92]

I think so, you'll probably have to drive around so it shows readiness, may take some time. There is a process, I'm not sure what it is. Do a combo of city and highway, cycle the ignition a few times. Lookup emissions readiness for a better idea

 

[Illsic_Design]

Yeah if you changed everything on the FF side then that would pretty much only leave the DME. Something happened to that input for sure is my guess, which means if any other FF systems use that same input you'll have the same problem as CruizinMax stated.

 

[Jeffman]

I think so, you'll probably have to drive around so it shows readiness, may take some time. There is a process, I'm not sure what it is. Do a combo of city and highway, cycle the ignition a few times. Lookup emissions readiness for a better idea

Keep in mind you cannot achieve 100% readiness with the MOTIV FF module wired. Evap will not be ready since the DMTL wire is used for the ethanol signal.

N54 - SOLVED: MOTIV / MHD FlexFuel Readiness Issues?

I seem to be having more trouble getting OBDII readiness now that I have MOTIV / MHD FlexFuel installed (N54 stock catted DPs ) . Both Catalyst: INCOMPLETE Evaporative System: INCOMPLETE Last year very similar tunes and presumably same toggles and passed. Anyone else having similar issues?

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