BM3 Flex Fuel Sensor / Re-tune

f93_gc · 12-27-2021, 12:34 PM

So over this past weekend. I had installed the BM3 Flex fuel kit and re-tuned the car from the E30 map to the Stage 2 multi map. I noticed that my cold starts are now gone, even after overwriting the cold start RPM to max of 1200, my cold start at 37 degrees F, still idled at roughly 700 rpm. I didn’t have this issue with the E30 tune. I can only assume this is part of the tune to help with cold starts on E85 since E85 is notorious for having a hard time starting in cold weather? Not a big worry, just would like some clarification if possible.

TopJimmy · 12-27-2021, 01:01 PM

Email PTF and ask. Let us know their answer.

Paul taught me E85 shouldn't use cold start since there's no need to heat up the cats. The flex tune may detect E% and disable it.

Xer0449 · 12-27-2021, 10:25 PM

Quote:

Originally Posted by TopJimmy

Email PTF and ask. Let us know their answer.

Paul taught me E85 shouldn't use cold start since there's no need to heat up the cats. The flex tune may detect E% and disable it.

Not to thread hijack, but I'd kill for a patch notes/list or something that detailed what features/tables are adjusted/toggled based on variables (like E content...)

mike@x-ph.com · 12-28-2021, 08:12 AM

Sub'd for an update on the cold start question

TopJimmy · 12-29-2021, 11:57 AM

Quote:

Originally Posted by mike@x-ph.com

Sub'd for an update on the cold start question

Quote:

Originally Posted by Xer0449

Quote:

Originally Posted by TopJimmy

Email PTF and ask. Let us know their answer.

Paul taught me E85 shouldn't use cold start since there's no need to heat up the cats. The flex tune may detect E% and disable it.

Not to thread hijack, but I'd kill for a patch notes/list or something that detailed what features/tables are adjusted/toggled based on variables (like E content...)

Answer from Halim:

All stage 1 tunes have coldstart active by default while stage 2 has it deactivated. So it's not changed by ethanol %, what is change is the fuel scalars.

mike@x-ph.com · 12-30-2021, 08:27 AM

Quote:

Originally Posted by TopJimmy

Answer from Halim:

All stage 1 tunes have coldstart active by default while stage 2 has it deactivated. So it's not changed by ethanol %, what is change is the fuel scalars.

hellokitty · 01-01-2022, 03:23 PM

Subscribed

f93_gc · 01-07-2022, 11:31 AM

Update on this:

Although i have reflashed the tune many times, for some reason today, flashing again seemed to fix it for now. Below are the settings i used:

Cold start: OEM
Cold Start RPM Override: 1200

hellokitty · 01-07-2022, 11:43 AM

Quote:

Originally Posted by f82_boi

Update on this:

Although i have reflashed the tune many times, for some reason today, flashing again seemed to fix it for now. Below are the settings i used:

Cold start: OEM
Cold Start RPM Override: 1200

Might have to give this a try to see if it helps me

hellokitty · 01-08-2022, 02:20 PM

Quote:

Originally Posted by f82_boi

Update on this:

Although i have reflashed the tune many times, for some reason today, flashing again seemed to fix it for now. Below are the settings i used:

Cold start: OEM
Cold Start RPM Override: 1200

I'm happy to report that setting cold start RPM to 1200 has fixed my idling problem on E85 flex fuel.

I would highly suggest others experiencing rough idling with cold start enabled to try this.

You are the man!!!!

12-27-2021, 12:34 PM	#1
f93_gc Private 40 Rep 72 Posts Drives: 2020 BMW M8 Competition Gran C Join Date: May 2020 Location: Los Angeles, CA iTrader: (0) Garage List 2020 BMW M8 Competi ... [9.87]	BM3 Flex Fuel Sensor / Re-tune So over this past weekend. I had installed the BM3 Flex fuel kit and re-tuned the car from the E30 map to the Stage 2 multi map. I noticed that my cold starts are now gone, even after overwriting the cold start RPM to max of 1200, my cold start at 37 degrees F, still idled at roughly 700 rpm. I didn’t have this issue with the E30 tune. I can only assume this is part of the tune to help with cold starts on E85 since E85 is notorious for having a hard time starting in cold weather? Not a big worry, just would like some clarification if possible.
	Appreciate 0 Tweet Quote

12-27-2021, 01:01 PM	#2
TopJimmy Major General 6162 Rep 5,530 Posts Drives: 2023 M3 Comp xDrive Join Date: Jul 2019 Location: Chester County, PA iTrader: (5)	Email PTF and ask. Let us know their answer. Paul taught me E85 shouldn't use cold start since there's no need to heat up the cats. The flex tune may detect E% and disable it. __________________ '18 F80 Base 6MT \| '19 F82 Exec DCT \| '18 F82 Comp Exec DCT \| '23 G80cx
	Appreciate 1 tomlong624.50 Quote

12-28-2021, 08:12 AM	#4
mike@x-ph.com BimmerPost Supporting Vendor 26010 Rep 194,257 Posts Drives: 07-335/12-328/18-M4/21-M4CP Join Date: Sep 2013 Location: Las Vegas iTrader: (23)	Sub'd for an update on the cold start question __________________ Check out our current sale by clicking on this link! https://x-ph.com/sale/ Phone number 702-494-9435
	Appreciate 0 Quote

01-01-2022, 03:23 PM	#7
hellokitty Brigadier General 2938 Rep 3,738 Posts Drives: '17 M3 ZCP DCT Join Date: Jul 2010 Location: Southern California iTrader: (2)	Subscribed __________________ 2017 F80 M3 ZCP / AA GESI DPs / Akrapovic Evo / BBS FI-R 19" / Bend Calibration ECUTEK Flex Fuel \| Bilstein B16 DDC + CS EDC / BMC Filters / BMS OCC / CSF HE / ESS CP / Nitto NT555R2 / PD Crank Hub / SPL Suspension / Uniden R7 / Wagner Top Mount IC 2021 Mini GP3 / BMC Filters / BM3 / Cary Jordan E30 / Wagner IC / Remus Race
	Appreciate 0 Quote

01-07-2022, 11:31 AM	#8
f93_gc Private 40 Rep 72 Posts Drives: 2020 BMW M8 Competition Gran C Join Date: May 2020 Location: Los Angeles, CA iTrader: (0) Garage List 2020 BMW M8 Competi ... [9.87]	Update on this: Although i have reflashed the tune many times, for some reason today, flashing again seemed to fix it for now. Below are the settings i used: Cold start: OEM Cold Start RPM Override: 1200
	Appreciate 0 Quote

Thread Tools	Search this Thread
Show Printable Version Email this Page	Search this Thread: Advanced Search