N54 Stock DME Flex Fuel
- Thread starter Jake@MHD
- Start date
I haven't heard of a fix yet but was hopping they might do a revision. Guess we'll have to wait and see.
Hi everyone,
Please be advised that if you are running a secondary LPFP, be sure to wire your relay by using a positive trigger. See chart below.
In order to do this exactly:
---
Background
My previous setup was using a ground trigger with the Hobbs switch out front. This causes voltage fluctuations in the DME as seen on the log below.
Issues with ground trigger up front. Pump gas will spike ECA voltage, causing ethanol to spike. Not good for this FF setup!
https://datazap.me/u/blisstik/log-1528169992?log=0&data=12-13-15-25
Even if you don't have this FF setup, I would still advise you to run a positive trigger with the Hobbs in the back. Who knows what issues this would cause by having voltage spikes in the DME whenever the secondary LPFP is triggered.
Please be advised that if you are running a secondary LPFP, be sure to wire your relay by using a positive trigger. See chart below.
In order to do this exactly:
- In the engine bay, remove the vacuum line in the brake booster then cap that off
- Route that line in the chargepipe or vacuum source
- In the trunk, locate the driver's side tail light panel and find the flapper valve. Disconnect the power connector and two hoses. You will probably need to extend the bottom vacuum hose to attach it to the Hobbs switch by getting a 1/8" female npt to barb adapter.
- Wire the relay as shown below. Pin #86 will go to one terminal of the Hobbs.
- The other side of the Hobbs will come from one of the wires from the flapper connector. It's the red/white wire.
---
Background
My previous setup was using a ground trigger with the Hobbs switch out front. This causes voltage fluctuations in the DME as seen on the log below.
Issues with ground trigger up front. Pump gas will spike ECA voltage, causing ethanol to spike. Not good for this FF setup!
https://datazap.me/u/blisstik/log-1528169992?log=0&data=12-13-15-25
Even if you don't have this FF setup, I would still advise you to run a positive trigger with the Hobbs in the back. Who knows what issues this would cause by having voltage spikes in the DME whenever the secondary LPFP is triggered.
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You don't need to go through all of that moving around and rewiring to the rear if you don't want to (though it is cleaner to have it all in the trunk / near the LPFP, and it's how I have mine).
If you prefer to keep the exhaust flap functional or the Hobbs in your engine bay, just wire like above and use a switched 12v in the engine bay for the "positive trigger source" to the Hobbs.
If you prefer to keep the exhaust flap functional or the Hobbs in your engine bay, just wire like above and use a switched 12v in the engine bay for the "positive trigger source" to the Hobbs.
They just came out with a new harness that has revised connectors made by nrw. Time will tell. Still no mention of the coils not fully seating though
ok ... so you mean to tell me you ordered the shit harness for $300 and got updated connectors? Site says nothing about a change. If this is available for sale it is unknown news to me and probably everyone else.
Filippo
Filippo
Thanks ... I just fired up a new thread on the harness stuff. Amazing how nothing has been said about this while people have been dangling with a broken product.
Filippo
Couple runs, 2011 335is DCT FBO
https://datazap.me/u/noguru/pulling?log=0&data=3-21
https://datazap.me/u/noguru/rolling?log=0&data=3-21
https://datazap.me/u/noguru/pulling?log=0&data=3-21
https://datazap.me/u/noguru/rolling?log=0&data=3-21
I saw that. I am not sure why. It is pretty humid here North of Detroit today so that might be a factor, IDK.
that 5" really isn't enough when you start pushing the stock turbos hard, probably contributing to the timing corrections. fueling looks good though. WGDC is high and you're maxing out the PID on boost control but still under target, but too be expected when pushing old stock turbos
side note- I'm in metro detroit too!
Thanks for the evaluation.
I was contemplating going to a 7" FMIC but I thought it might be overkill.
So looks like new FMIC and new Turbos are in my future
I am in Waterford if you know where that is.
Very good points. People need to remember that the OTS maps aren't going to be 100% perfect for everyones car either. We wanted OTS FF logs just to make sure everything is functioning properly (flash process, encryption, blending to the OTS E50 map, etc). So far all of that looks great.
I think there will be one small tweak to the fuel interpolation for lower E blends, one more round of logs then good to go pending no issues
