2EF4 Error Code

Frozen Fractals · 10-28-2015, 12:28 PM

I was scanning for ghost codes on INPA yesterday and came across a 2EF4 error code. I ran my generic code reader on it too and it came up with a P0128 Coolant Temperature below control range error as well. I am assuming my thermostat is shot? I don't have SES light.

Out of curiosity, I plugged in my OBD2 BT adapter and ran the Torque app off of my tablet on the way to work this morning. I monitored the temperature along the way and it basically sat between 80-86C most of the way. Ambient was around 15C. Drive consists of 5 miles divided highway (55-60 mph), followed by 5 miles of local roads (a lot of stop and go), and finally 5 miles of actual highway (80 mph). I read that the engine is supposed to operate around 95-97C. Does it seem that my thermostat is stuck open and not allowing the car to warm up to the optimal temps?

MachWon · 10-28-2015, 01:22 PM

Subbed. I've had this code too for a long time now.

fravel · 10-28-2015, 02:05 PM

I don't remember what the actual code was when my thermostat failed, but I didn't have a check engine light either. Come to think of it I don't even remember what prompted me to check it :/

norsairius · 10-28-2015, 02:30 PM

Based on the pic in this thread, looks like the thermostat could be stuck open:
http://www.xoutpost.com/bmw-sav-foru...2ef4-2f09.html

My assumption is that it's time to replace it.

Frozen Fractals · 10-28-2015, 03:19 PM

Word. That's what I came the conclusion to as well. Question: I am on the original thermostat and water pump. When I do the thermostat, should I also change the water pump as well even if there are no signs of it failing? The car has 114k on it. I would like to change it, but I am not sure it's a preventive maintenance thing or not considering the price of one is $400.

fravel · 10-28-2015, 04:00 PM

I didn't bother, I just changed the thermostat and the coolant. I'm with you. For $400 I can wait.

Frozen Fractals · 10-28-2015, 04:43 PM

Are there any good DIYs out there on thermostat replacement? I've heard they're a PITA to replace since you cotta go through a sway bar and some PS hoses. It also doesn't help any that's it's tucked in above the water pump.

hassmaschine · 10-28-2015, 06:26 PM

sounds like your thermostat is stuck open. Unless you were driving at WOT all the time, the temp should run significantly hotter than 80-86c.

Efthreeoh · 10-29-2015, 05:05 AM

2EF4 means the heater core in the t-stat is/has failed. What it means is the engine warmup cycle for low emissions maybe faulty. Normally it throws an OBDII trouble code (SES light). Only fix is to replace the t-stat.

Kyle192 · 02-28-2021, 11:44 AM

P0030
P2D0D
P2EFE
P2F04
P2EE0
P2EF4

I was driving home and all the sudden my engine light came on and my car was shaking a lot and reduced power came on.
Can anyone help please

10-28-2015, 12:28 PM	#1
Frozen Fractals First Lieutenant 163 Rep 321 Posts Drives: 2018 540i xDrive Join Date: Jun 2015 Location: US / China iTrader: (2)	2EF4 Error Code I was scanning for ghost codes on INPA yesterday and came across a 2EF4 error code. I ran my generic code reader on it too and it came up with a P0128 Coolant Temperature below control range error as well. I am assuming my thermostat is shot? I don't have SES light. Out of curiosity, I plugged in my OBD2 BT adapter and ran the Torque app off of my tablet on the way to work this morning. I monitored the temperature along the way and it basically sat between 80-86C most of the way. Ambient was around 15C. Drive consists of 5 miles divided highway (55-60 mph), followed by 5 miles of local roads (a lot of stop and go), and finally 5 miles of actual highway (80 mph). I read that the engine is supposed to operate around 95-97C. Does it seem that my thermostat is stuck open and not allowing the car to warm up to the optimal temps?
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10-28-2015, 01:22 PM	#2
MachWon Private First Class 25 Rep 197 Posts Drives: 2007 335i 6mt. JB4 + CDP's. Join Date: Mar 2015 Location: . iTrader: (0)	Subbed. I've had this code too for a long time now.
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10-28-2015, 02:05 PM	#3
fravel Colonel 1645 Rep 2,494 Posts Drives: Monaco Blue '06 330i Join Date: Aug 2012 Location: The Nasti 'Nati iTrader: (1)	I don't remember what the actual code was when my thermostat failed, but I didn't have a check engine light either. Come to think of it I don't even remember what prompted me to check it :/ __________________
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10-28-2015, 02:30 PM	#4
norsairius Foodie and Gearhead 102 Rep 733 Posts Drives: 2011 335i xDrive Sedan Join Date: Mar 2013 Location: MN iTrader: (0) Garage List 2011 BMW 335i xDriv ... [9.50]	Based on the pic in this thread, looks like the thermostat could be stuck open: http://www.xoutpost.com/bmw-sav-foru...2ef4-2f09.html My assumption is that it's time to replace it. __________________ 2011 335i xDrive Sedan, Deep Sea Blue w/Oyster Interior
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10-28-2015, 03:19 PM	#5
Frozen Fractals First Lieutenant 163 Rep 321 Posts Drives: 2018 540i xDrive Join Date: Jun 2015 Location: US / China iTrader: (2)	Word. That's what I came the conclusion to as well. Question: I am on the original thermostat and water pump. When I do the thermostat, should I also change the water pump as well even if there are no signs of it failing? The car has 114k on it. I would like to change it, but I am not sure it's a preventive maintenance thing or not considering the price of one is $400.
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10-28-2015, 04:00 PM	#6
fravel Colonel 1645 Rep 2,494 Posts Drives: Monaco Blue '06 330i Join Date: Aug 2012 Location: The Nasti 'Nati iTrader: (1)	I didn't bother, I just changed the thermostat and the coolant. I'm with you. For $400 I can wait. __________________
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10-28-2015, 04:43 PM	#7
Frozen Fractals First Lieutenant 163 Rep 321 Posts Drives: 2018 540i xDrive Join Date: Jun 2015 Location: US / China iTrader: (2)	Are there any good DIYs out there on thermostat replacement? I've heard they're a PITA to replace since you cotta go through a sway bar and some PS hoses. It also doesn't help any that's it's tucked in above the water pump.
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10-28-2015, 06:26 PM	#8
hassmaschine Major General 3975 Rep 7,215 Posts Drives: "NBO" 330i Join Date: Jun 2014 Location: earth iTrader: (0)	sounds like your thermostat is stuck open. Unless you were driving at WOT all the time, the temp should run significantly hotter than 80-86c.
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10-29-2015, 05:05 AM	#9
Efthreeoh General 17428 Rep 18,801 Posts Drives: The E90 + Z4 Coupe & Z3 R'ster Join Date: May 2012 Location: Virginia iTrader: (0)	2EF4 means the heater core in the t-stat is/has failed. What it means is the engine warmup cycle for low emissions maybe faulty. Normally it throws an OBDII trouble code (SES light). Only fix is to replace the t-stat. __________________ A manual transmission can be set to "comfort", "sport", and "track" modes simply by the technique and speed at which you shift it; it doesn't need "modes", modes are for manumatics that try to behave like a real 3-pedal manual transmission. If you can money-shift it, it's a manual transmission. "Yeah, but NO ONE puts an automatic trans shift knob on a manual transmission."
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02-28-2021, 11:44 AM	#10
Kyle192 Registered 0 Rep 2 Posts Drives: Bmw 335xi Join Date: Feb 2021 Location: Mass iTrader: (0)	Need help figuring out codes P0030 P2D0D P2EFE P2F04 P2EE0 P2EF4 I was driving home and all the sudden my engine light came on and my car was shaking a lot and reduced power came on. Can anyone help please
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