N54 Stock DME Flex Fuel

[Jake@MHD]

Urgent- Can I flash back to stock with fuel flex hardware installed?

You can, but will get a code or two. You may have to clear it each time you start the car, unsure.

Got everything in the tune sorted and testing different concentrations of E. For a moment on this latest map, I feared the fluctuating load issue was back, but I see that it is the tune responding to the change in ethanol percentage. It's really odd that it went to 100% ethanol for that 300 rpm span.

@jyamona, is that normal that it would be that responsive, or should there be some sort of "smoothing". Since there is pretty much no chance that I had 100% ethanol at that moment, what would your suggestion be? Water contamination? My ethanol is a couple weeks old, but stored in an airtight container with no outside exposure. That's my suspicion for now unless someone has any other ideas.

E42 - MMP S3 - VRSF Race - E90 6MT
https://datazap.me/u/langsbr/log-1530762584?log=2&data=3-12-18-19-23

Do you have PI or a second LPFP? And is your Continental E-sensor in the fuel feed line?

Yeah that could be dangerous, if you're running a lower E content and it jumps to 100% it'll run pretty aggressive boost/timing/fueling. Given that ethanol sensor voltage also spikes there I would start by looking into the wiring. Where did you ground it and where are you getting power from?

E content spikes because the sensor voltage spikes, one is a lookup via table from the other. It is most likely a wiring issue, the problem is figure out what. It seems the Continental sensors are very finicky with their grounds. If you have anything else grounded to the same spot (like AIC or 2nd LPFP), when it activates it has been shown to cause a spike like this. Also, as Galileo posted above, if using a 2nd LPFP w/ hobbs trigger, you want to only use the hobbs as a positive trigger to the relay and hookup the grounds directly to batt.

 

[langsbr]

I'm using the Motiv short feed line kit, no PI or second LPFP. I have the Flex fuel module grounded on the ground stud that the instructions listed. I'll double check it today and make sure nothing has some loose.

 

[Jake@MHD]

I hadn't even thought of it in the terms of running 93 and it spiking to 40 or so. That would indeed raise all the targets. I was thinking it had to be water since it spiked all the way to 100%. I have it grounded at the point in the instructions, and power via the tap provided on the green connector. It was only for a 300 rpm span, which was likely less than a second, so perhaps wiring isn't the cause.

It didn't spike to actual 100% ethanol from the ECA, it read as 100% in MHD because the table is setup to treat the error voltage range (4V+) as 100% ethanol. Your tuner can change this to treat it as 0% E, or anything else. Tuning tip: using the error voltage range as 100% or 0% E are the "correct" choices, as those conditions should never really exist in your fuel tank. That then allows the individual interpolation tables (fuel, timing, and load) to handle the error condition differently.

Other ECA info:
Actual 100% ethanol from the sensor would be around 3V.
Water contamination would be around 5V.

Your log looked to be trending to 4.5V, which is usually short to ground on continental ethanol sensor.

 

[Payam@BMS]

Actual 100% ethanol from the sensor would be around 3V.
Water contamination would be around 5V.

This is really cool, very important to know the difference.

 

[fmorelli]

This make so much sense for easily disconnecting the FlexFuel kit when desired

Thank @barry@3DM not me lol. That one was his idea.

@barry@3DM can you verify the drawing above? I seem to recall we might have swapped a connector (male to female) so everything OCD lined up , though wiring is the same ...

Filippo

 

[barry@3DM]

Filippo,

This make so much sense for easily disconnecting the FlexFuel kit when desired - whether back to stock or for experimenting with new tunes. I’d like to do this too, and I’m sure others are as well. If it’s not too much trouble, can you please share a link to where we can also purchase these connectors?

Thanks again for your valuable participation to the forum and to the N54 community.

@Jeffman @fmorelli

This is a diagram if not using Port Injection. Also note the DME plug numbers are x60002 and x60005. Plugs are Deutsch DTM aka "mini". I used a 3 pin receptacle on DME side and plugs on chassis/Flex Fuel sides. Power and ground were run to the chassis directly and not through any plugs.

Note on the Deutsch connectors. The pins come in multiple options. There is open barrel and closed barrel nickel or gold. The closed barrel option requires a very expensive crimp tool but the open barrel option you can crimp with any open barrel crimp tool. Also, when creating a jumper wire, it requires two wires to go into one pin. (the yellow wire in the diagram) When doing this the best practice is to use open barrel pins. You can shove two wires into one closed barrel but it is not a good idea because those crimps will crush the wires too much which can lead to wire failure over time.

This is my recommendation for open barrel crimp tool: I've found the ratcheting crimp tools don't work well on the tiny DTM pins which is why I recommend this one.
https://www.amazon.com/gp/product/B002TKG11G/ref=oh_aui_detailpage_o06_s00?ie=UTF8&psc=1

If you are going to do a lot of wiring on your car then spring for one of the closed barrel crimp tools:
Search for PT-48-00 or HDT-48-00

For Deutsch connectors there are many places: (I keep them in stock but don't have them up for sale yet)
https://www.milspecwiring.com/
https://www.prowireusa.com/
http://www.deutschconnector.com/

Hope this helps!
Barry

 

[baturbo]

You can, but will get a code or two. You may have to clear it each time you start the car, unsure.

By way of update. Flashed the car back to stock with MHD due to going into BMW for some recalls. Drove there and back (60 mins total) no errors or issues, apart from the lack of power that comes with stock.

 

[R.G.]

Yo, the harness replaces the existing pins in the sub connectors? Existing pins just null at that point, correct?

Anyone want to chime in on this for me? Just need confirmation.

Two of the pin #s already have an existing pin. Trying to get confirmation those simply are removed and are no longer used.

 

[Jake@MHD]

Anyone want to chime in on this for me? Just need confirmation.

Two of the pin #s already have an existing pin. Trying to get confirmation those simply are removed and are no longer used.

One (where the ECA output signal goes to DME) is no longer used. The other (assuming you are using PI?) is the boost signal. The existing wire is an input to the ECA.

 

[R.G.]

One (where the ECA output signal goes to DME) is no longer used. The other (assuming you are using PI?) is the boost signal. The existing wire is an input to the ECA.

Ok. So green from harness replaces existing connection
yellow is actually a Y-tap now that I look closely, so got that.
And blues clues goes to AIC (yes, car is running PI)

Thanks

 

[Jeffman]

@Jeffman @fmorelli

This is a diagram if not using Port Injection. Also note the DME plug numbers are x60002 and x60005. Plugs are Deutsch DTM aka "mini". I used a 3 pin receptacle on DME side and plugs on chassis/Flex Fuel sides. Power and ground were run to the chassis directly and not through any plugs.

Note on the Deutsch connectors. The pins come in multiple options. There is open barrel and closed barrel nickel or gold. The closed barrel option requires a very expensive crimp tool but the open barrel option you can crimp with any open barrel crimp tool. Also, when creating a jumper wire, it requires two wires to go into one pin. (the yellow wire in the diagram) When doing this the best practice is to use open barrel pins. You can shove two wires into one closed barrel but it is not a good idea because those crimps will crush the wires too much which can lead to wire failure over time.

This is my recommendation for open barrel crimp tool: I've found the ratcheting crimp tools don't work well on the tiny DTM pins which is why I recommend this one.
https://www.amazon.com/gp/product/B002TKG11G/ref=oh_aui_detailpage_o06_s00?ie=UTF8&psc=1

If you are going to do a lot of wiring on your car then spring for one of the closed barrel crimp tools:
Search for PT-48-00 or HDT-48-00

For Deutsch connectors there are many places: (I keep them in stock but don't have them up for sale yet)
https://www.milspecwiring.com/
https://www.prowireusa.com/
http://www.deutschconnector.com/

Hope this helps!
Barry

Thanks Barry!
Thanks Filippo!
Very helpful!

 

[Hill'n'toe]

I've got a problem with FF. I was on OTS FF 98RON everything worked fine. Yesterday, I flashed with a protune map and just after the ethanol content is 0%.
Any idea ?

 

[Jake@MHD]

I've got a problem with FF. I was on OTS FF 98RON everything worked fine. Yesterday, I flashed with a protune map and just after the ethanol content is 0%.
Any idea ?

Hi, who is your tuner? Sounds like the screwed something up.

 

[Hill'n'toe]

Hi, who is your tuner? Sounds like the screwed something up.

Reply in private.

 

[fmorelli]

Gratuitous Flex Fuel velvet hammer photos ...

Filippo

 

[Abacus38]

Gratuitous Flex Fuel velvet hammer photos ...

Filippo

View attachment 13233


View attachment 13232

View attachment 13234

Your car is beautiful m8

 

[NoGuru]

Morning pulls at E47
335is DCT, FBO, just rolled 60K on the odometer. https://datazap.me/u/noguru/july-9th-morning?log=0&data=3-21

 

[Lifestyler]

Works the ff with PI 6466st build engine dual 450walbros MHD flash only nice?
(Wotbox also installed)

Then U Install Mine today .
Any other st Guys Usingen FF already ?

 

[NoGuru]

This is not my normal morning pull. I had to much traffic to do WOT but..something is wrong.
I thought I herd boost leaking and looking at the logs I might be correct.

Boost target is pretty far from boost. https://datazap.me/u/noguru/low-boost?log=0&data=3-4-21

 

[NoGuru]

I'm glad to report I found my boost leak right away and fixed it. The charge pipe that connects to the piping going to the FMIC came off. Easy fix thankfully.
Tuesday evening pull after fix https://datazap.me/u/noguru/tuesday-afternoon?log=0&data=3-13-21

Wednesday morning pull E50 https://datazap.me/u/noguru/wed-morning-after-boost-leak-fix?log=0&data=3-4-21