N54 Stock DME Flex Fuel

[Mon54ster]

Problem solved! The flex fuel module was sent with incorrect wiring. There seems to be two board configurations (old and new). I was sent an old board with wiring for the New board. Jake@motiv sent me the repin instructions and is now working flawlessly.

 

[Jake@MHD]

Glad to hear it! Enjoy!

 

[Illsic_Design]

Are you running a tune for ethanol yet?

 

[e92xiSS]

Are you running a tune for ethanol yet?

I am running flex fuel OTS Map for now. I will be getting full custom tune from jake@motiv as soon as this issue is cleared up but in meanwhile he is helping me to see if its the map issue.

 

[Prolifik123]

@Mon54ster do you have a copy of pins to change? i have the same issue i think

 

[dwspen01]

I have a 2009 Z4 and installed the Motiv Flex Fuel module this winter with the MHD flex module and a custom tune. It was showing ~45% ethanol and I figured that was because of winter blend E85 a few months ago. I was surprised when I just filled up again it was showing 46.3% but I tested the fuel in a test tube with water and it was 80-85% ethanol. My ECA Voltage reads 2.38v on the MHD app. I sent an email to Motiv but am waiting to hear back. Any thoughts/suggestions on what the issue could be?

 

[Jern54]

Check your ground connection.
After several tests my sensor had a offset of approx 8%. After taking samples out of the fuel tank I made some changes in voltage scaling with my tuner.

 

[mj6234]

Shot over an email to MOTIV/MHD, but having the issue where ethanol reading goes to 100% and ECA voltage goes to 4.79. See attached for logs/screenshots. Seems to happen just before 3000 rpm every time and not as soon as I got WOT.

 

[langsbr]

Shot over an email to MOTIV/MHD, but having the issue where ethanol reading goes to 100% and ECA voltage goes to 4.79. See attached for logs/screenshots. Seems to happen just before 3000 rpm every time and not as soon as I got WOT.

Check your grounds. When it goes to a 100% that's usually an indication of the ground not being perfect.

 

[mj6234]

Check your grounds. When it goes to a 100% that's usually an indication of the ground not being perfect.

In this case, it is just the ground on the Motiv FF box right? The one going to the post near the windshield wiper fluid?

 

[langsbr]

Yes - I moved mine to one of the shock tower bolts after removing some paint under the bolt. Much better consistency.

 

[mj6234]

Yes - I moved mine to one of the shock tower bolts after removing some paint under the bolt. Much better consistency.

Appreciate the input. I was trying to figure out where the DME was grounded (maybe on the firewall somewhere)? I cant tell what else is on the ground location where they recommended to install it, but wondering if there is some interference there or something.

I feel like the supplied ground wire was irrationally short, so might have to extend it to go elsewhere.

 

[mj6234]

Same deal with the shock tower post. Rechecked all wiring, seems fine. Is there anything else that is part of the OEM car that could cause this type of issue? I dont have a secondary pump, no meth pump, I looked at the DME wiring schematic, and the DME is grounded to that point by the windshield wiper reservoir.

I assume it isnt some kind of grounding strap problem. I did notice the issue always appears around the same RPM (2900-3000) in 3rd gear at least.

 

[mj6234]

Same deal with the shock tower post. Rechecked all wiring, seems fine. Is there anything else that is part of the OEM car that could cause this type of issue? I dont have a secondary pump, no meth pump, I looked at the DME wiring schematic, and the DME is grounded to that point by the windshield wiper reservoir.

I assume it isnt some kind of grounding strap problem. I did notice the issue always appears around the same RPM (2900-3000) in 3rd gear at least.

OK guys, just to close the loop here - finally got resolution. After trying a new ECA + harness and still having the issue I was not hopeful. After a suggestion from a buddy, I moved the power source over to the +12v jump post right by the DME box - just to see if the issue disappeared. As soon as I did that, the ECA read steady with no fluctuations under WOT!!!

At that point, I assumed it was a bad tap. So I pulled off the positap and carefully retapped the same wire. Issue still present. Came back home and moved the positap to the other wire under the green power connector in the DME box. Issue gone!!! So I am not sure which power wire is used for what exactly, but it appears it DOES matter which one you use. At least in my case it did.

Other things I learned. In the absence of a signal from the ECA, the DME pulls the voltage on that pin up to 5v, which is 100% ethanol. In your tune, just make sure the >4v cell in the table is set to something safe. The default after running the FF BIN conversion is 100% in that cell, I will be setting mine to 0%. I confirmed this by disconnecting power to the ECA and logging with MHD when the car was not started. The DME showed 4.39v from the ECA and 100% ethanol in that case.

@NoGuru, I think you were not able to get resolution on a similar issue correct? Not sure if you want to go reinstall and test my findings to see if it worked in your case. I know I have taken everything apart and put it back together a lot trying to get this sorted out.

I will say MOTIV was responsive to my support request, sent out a new ECA and harness to help me, and were otherwise great to deal with. Props to them for listening and doing what they could to help me.

 

[NoGuru]

Yeah my issue was never resolved after working on it for about a year. I could slap everything back in but I'm just running a full Ethanol tune now so no need to.
I have a Fuel IT Bluetooth E analyzer setup on the line now as well.

Can you post some pics or diagram of your findings?

 

[Jeffman]

Well guys, the day is finally here. The MHD FlexFuel module is ready! For a short period of time, we are going to run it as a "closed" beta that will be open to all verified purchasers of the official MHD / Motiv ECA (available here.) As this is such an extensive feature, this allows us to have a more controlled test group as well as an easier way to receive and collate feedback. Additionally, this forum will continue to serve as the main area for discussion.

Getting Involved:
In order to be added to the beta group, first be sure to register as a tester for MHD here. Then contact either Jake H, Chris, or myself and provide the Google account that you use for MHD. Once you are verified as having purchased the ECA, I will add you to the beta group and you will see the MHD update available.

OTS Users:
The main feedback we are looking for is logs of the MHD OTS FF maps running various ethanol blends. If you wish to use the OTS FlexFuel maps, you must have the following:

• Stage 1 or stage 2 pump gas map pack
• E85 mix map pack
• Flex Fuel module
• Motiv ECA
• Flasher
• Logger

If you meet the above conditions, all you need to do is flash a stage 1 or stage 2 V8 pump map after your MHD app is updated. MHD will automatically add the ethanol tables, setup interpolation, etc.
NOTE 1: OTS Flex Fuel is only applicable when flashing a V8 map
NOTE 2: Boost targets, HP, and TQ will taper off steeply back to the pump gas levels above E50 while fueling will remain maxed for safety. So while you technically can fill up with greater than E50, there is zero benefit and actually a detriment to power.

Pro-Tune Users:
You guys should be good to go, just wait for an updated map from your tuner and purchase the FlexFuel module in MHD.

Self Tuners and Pro-Tuners:
The GitHub has now been updated with everything needed. Please be sure to continue to download the full zip file. You will see a new folder inside, FlexFuel, which has three sub folders:

• Calibration Format Tool - you must drag and drop your bin on this exe in order to correctly format it for use with the FlexFuel XDFs. It will spit out a suitable file with an "_FF" suffix. If you do not do this step, the bin will not look correct in TunerPro with the Flex Fuel XDF, and MHD will not apply the FF logic
• ECA Firmware Updater - this is not needed for now as all ECA have shipped with the latest firmware. This is more for future proofing.
• New XDFs - in addition to the main flex fuel tables, warm-up enrichment (pump and flex) is also included so your cold start E85 issues can be completely fixed

General:
There will be 5 new parameters available to log in MHD: ECA Voltage, Ethanol Content, Fuel Interpolation %, Timing Interpolation %, and Load Interpolation %.

I'm very happy to finally get this out to you guys, I know it's been a long road. Enjoy!

Jake’s instructions say to flash a V8 map for OTS Flex fuel. Will this now work with the new V9 maps?

 

[Jeffman]

Jake’s instructions say to flash a V8 map for OTS Flex fuel. Will this now work with the new V9 maps?

Answering my own question: So I just tried V9 and FlexFuel. It flashed fine and seems to run fine. No logs yet since I’m still readapting my 6HP after the mechatronics solenoids and sleeves maintenance.

 

[Jake@MHD]

Yes, all maps newer than V8 will support it as well.

 

[jakeg]

Same deal with the shock tower post. Rechecked all wiring, seems fine. Is there anything else that is part of the OEM car that could cause this type of issue? I dont have a secondary pump, no meth pump, I looked at the DME wiring schematic, and the DME is grounded to that point by the windshield wiper reservoir.

I assume it isnt some kind of grounding strap problem. I did notice the issue always appears around the same RPM (2900-3000) in 3rd gear at least.

If you have upgraded coil packs the 12v power wire should be moved. I had the same issue after I installed my pr coils and enabled them in MHD. I just found another 12V power wire and used it. Worked perfectly after.

 

[Jeffman]

Just checked my ethanol content after running a year on Shell 93 pump gas ….reading zero 0% … it should be ~10%….ECA is 0.75V. Obviously a problem occurred. I’m also getting a recurring 2B3B error even after replacing the DMTL pump. I’m suspecting a leak at the wired ethanol sensor. Anybody else have these issues? Any suggestions?