Leaving E30 mix in tank + winter

Prak903 · 11-24-2022, 09:55 AM

Hi all,

Recently flashed BM3 Stage 2+ E30 and enjoying it. My concern is keeping it in the tank for 2-3 weeks at a time, I usually don't drive too much in the city. Also don't know the effects too much on what freezing temps have on ethanol, but heard it can cause more wear. Is it safe to keep e30 mix that long in the tank? Otherwise I may have to just go back to 93.

freakystyly · 11-24-2022, 11:57 AM

Ethanol (alcohol) is an antifreeze. Send it

Ethanol would eat at fuel lines and such on pre-1990 technology cars, but that is outdated obviously. It does absorb water from the air.. but that shouldn't be an issue on a closed system.

blacksapphire440i · 11-24-2022, 02:42 PM

Quote:

Originally Posted by Prak903

Hi all,

Recently flashed BM3 Stage 2+ E30 and enjoying it. My concern is keeping it in the tank for 2-3 weeks at a time, I usually don't drive too much in the city. Also don't know the effects too much on what freezing temps have on ethanol, but heard it can cause more wear. Is it safe to keep e30 mix that long in the tank? Otherwise I may have to just go back to 93.

You should be good for letting it sit for at least a month

G.Newt · 11-24-2022, 03:04 PM

2-3 weeks ain't shit. Send it my boy.

Skyhigh · 11-24-2022, 03:41 PM

The potential issue is not freezing. It is phase separation! In winter humidity and low temperatures cause condensation, thus higher water content in the tank. Water and ethanol blend. Given time, phase separation occurs, where you'd have a mixture of water and Ethanol at the bottom of your tank and pure gasoline above that.

https://petroclear.com/resources/dont-be-phased.php

I only do E10 fuel blend, but just for the sake of it, now that I will not be driving the car for more than a month, I stopped adding E to have as clean gasoline as possible. Maybe excessive, but it costs nothing, just some preventive thinking. With E30 I'd be much more careful, depending on your weather conditions and inactivity time.

mike@x-ph.com · 11-25-2022, 08:08 AM

I never had any issues, and I travel for weeks sometimes. I also run a mix of E40.

weehe126 · 11-25-2022, 05:00 PM

The issue comes running straight E85 and letting it sit for months. No issues with E30.

Prak903 · 11-25-2022, 09:03 PM

Thanks guys. Will keep it in the tank - probably run 93 through it every 2-3 fills or so.

11-24-2022, 09:55 AM	#1
Prak903 Second Lieutenant 188 Rep 271 Posts Drives: 2018 440i xDrive Gran Coupe Join Date: May 2022 Location: Chicago, IL / Milwaukee, WI iTrader: (0) Garage List 2018 BMW 440i xDriv ... [9.50]	Leaving E30 mix in tank + winter Hi all, Recently flashed BM3 Stage 2+ E30 and enjoying it. My concern is keeping it in the tank for 2-3 weeks at a time, I usually don't drive too much in the city. Also don't know the effects too much on what freezing temps have on ethanol, but heard it can cause more wear. Is it safe to keep e30 mix that long in the tank? Otherwise I may have to just go back to 93.
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11-24-2022, 11:57 AM	#2
freakystyly Lieutenant Colonel 2984 Rep 1,795 Posts Drives: F22 B58 6MT Join Date: May 2016 Location: Ontario iTrader: (0)	Ethanol (alcohol) is an antifreeze. Send it Ethanol would eat at fuel lines and such on pre-1990 technology cars, but that is outdated obviously. It does absorb water from the air.. but that shouldn't be an issue on a closed system.
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11-24-2022, 03:04 PM	#4
G.Newt Major 811 Rep 1,453 Posts Drives: CT4-V Blackwing 6MT Join Date: Feb 2017 Location: CO -> TX iTrader: (0)	2-3 weeks ain't shit. Send it my boy. __________________ 2022 CT4-V Blackwing 6-speed SOLD: 2016 340i xDrive 6-speed DAW v2.5 turbo E40 \| Dorch S2 \| VRSF DP \| MST intake \| AWE catback \| 335is clutch \| CSF heat exchanger \| RK Autowerks intake manifold \| Orange M Perf Brake Kit \| KW Street Comfort coilovers \| GTS taillights V2
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11-24-2022, 03:41 PM	#5
Skyhigh Brigadier General 1882 Rep 3,869 Posts Drives: BMW F36 Join Date: Apr 2018 Location: Europe iTrader: (0)	The potential issue is not freezing. It is phase separation! In winter humidity and low temperatures cause condensation, thus higher water content in the tank. Water and ethanol blend. Given time, phase separation occurs, where you'd have a mixture of water and Ethanol at the bottom of your tank and pure gasoline above that. https://petroclear.com/resources/dont-be-phased.php I only do E10 fuel blend, but just for the sake of it, now that I will not be driving the car for more than a month, I stopped adding E to have as clean gasoline as possible. Maybe excessive, but it costs nothing, just some preventive thinking. With E30 I'd be much more careful, depending on your weather conditions and inactivity time. __________________ "Large increases in cost with questionable increases in performance can be tolerated only in cars and women."
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11-25-2022, 08:08 AM	#6
mike@x-ph.com BimmerPost Supporting Vendor 24174 Rep 190,750 Posts Drives: 07-335/12-328/18-M4/21-M4CP Join Date: Sep 2013 Location: Las Vegas iTrader: (23)	I never had any issues, and I travel for weeks sometimes. I also run a mix of E40. __________________ Check out our current sale by clicking on this link! https://x-ph.com/sale/ Phone number 702-494-9435
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11-25-2022, 05:00 PM	#7
weehe126 Brigadier General 1161 Rep 3,189 Posts Drives: 2017 340i Join Date: Apr 2014 Location: San Antonio iTrader: (2)	The issue comes running straight E85 and letting it sit for months. No issues with E30.
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11-25-2022, 09:03 PM	#8
Prak903 Second Lieutenant 188 Rep 271 Posts Drives: 2018 440i xDrive Gran Coupe Join Date: May 2022 Location: Chicago, IL / Milwaukee, WI iTrader: (0) Garage List 2018 BMW 440i xDriv ... [9.50]	Thanks guys. Will keep it in the tank - probably run 93 through it every 2-3 fills or so.
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