Error codes 4B90, 4BC2, 4BC7, 4BA1 and EML

mjn77 · 09-20-2017, 05:33 AM

I've got an "increased emissions" error on the idrive, check engine light and four fault codes.

The error codes also show that the intake air temperature is anywhere between minus 12 and minus 48 degrees.

I'm right in thinking i've a duff MAF sensor?

robnitro · 09-20-2017, 06:37 AM

Maf doesn't report iat, the iat sensor is on the pipe that goes from ic to the intake throttle/egr

mjn77 · 09-20-2017, 06:47 AM

So maybe just the temperature sensor?

TDIwyse · 09-20-2017, 06:55 AM

Quote:

Originally Posted by robnitro

Maf doesn't report iat, the iat sensor is on the pipe that goes from ic to the intake throttle/egr

Actually, the MAF does report IAT. The CACT's are reported from the sensor you mention. Then there's also an AAT sensor that reports ambient air temps.

If your IAT's are that far off, it's most likely your MAF is having problems.

mjn77 · 09-20-2017, 07:13 AM

Here are the full error codes.....

TDIwyse · 09-20-2017, 07:33 AM

Quote:

Originally Posted by mjn77

Here are the full error codes.....

Your battery voltage is extremely low in many of those reports ... is your battery in need of replacement? The battery issue should be fixed first before diagnosing anything else because that low of voltage could be causing all kinds of issues with the cars electronics.

mjn77 · 09-20-2017, 07:35 AM

As far as i'm aware it's the original battery that came with the car, MY 09/2011.

Yozh · 09-21-2017, 02:53 AM

Agree on the battery. But also your MAF is done.

robnitro · 09-21-2017, 09:13 AM

If the engine is running and voltage is low, the alternator is not working properly.

mjn77 · 09-21-2017, 09:19 AM

Quote:

Originally Posted by robnitro

If the engine is running and voltage is low, the alternator is not working properly.

No, the errors occured with the ignition on, but engine off.

robnitro · 09-21-2017, 01:05 PM

I see engine speed around 660 and 965 in those snap shots with voltages of 11.24 and 12.06v. The battery shouldn't be below 13v with engine running.

mjn77 · 09-21-2017, 01:39 PM

Ok, will have the alternator checked as well.

TDIwyse · 09-21-2017, 01:57 PM

Quote:

Originally Posted by robnitro

...The battery shouldn't be below 13v with engine running.

Unless the harmonic balancer issue has happened to him. OP, you may want to check your balancer as well... http://www.e90post.com/forums/showthread.php?t=1255658

mjn77 · 10-01-2017, 10:49 AM

MAF replaced, all error codes cleared. I read that the car will adjust to the new MAF by itself within 30miles/50KM, but i'm fairly sure my MPG is still slightly lower than it should be, but i've not crunched the numbers yet.

A quick read online shows that we don't need to reset the MAF adaptations unless there is a note in the box (of the new MAF) that say to do it.

Yozh · 10-01-2017, 11:37 PM

BMW says you need to reset MAF adaptations and mean quantity adaptations when a new MAF is fitted. This will also explain your lower mileage.

mjn77 · 10-02-2017, 12:47 AM

Quote:

Originally Posted by Yozh

BMW says you need to reset MAF adaptations and mean quantity adaptations when a new MAF is fitted. This will also explain your lower mileage.

Thanks. Will crack the laptop out later on.

09-20-2017, 05:33 AM	#1
mjn77 Lieutenant Colonel 1073 Rep 1,957 Posts Drives: E90 M3 LCI Jerez Black Join Date: Apr 2015 Location: Herts, UK iTrader: (2) Garage List 2011 BMW M3 [0.00]	Error codes 4B90, 4BC2, 4BC7, 4BA1 and EML I've got an "increased emissions" error on the idrive, check engine light and four fault codes. The error codes also show that the intake air temperature is anywhere between minus 12 and minus 48 degrees. I'm right in thinking i've a duff MAF sensor? __________________ // E90 M3 LCI DCT in Jerez Black with Fox Red Leather // Alcantara Trim // ST XTA Coilovers // 1.75 Exhaust Mod // Pinnacle Undertray // @jerez.black.e90.m3 // Euro Alpine Road Trips 2014 2016 2017 2018 2019 2022
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09-20-2017, 06:37 AM	#2
robnitro Captain 160 Rep 803 Posts Drives: x5 35d e70 2011 Join Date: Sep 2016 Location: NYC area iTrader: (0)	Maf doesn't report iat, the iat sensor is on the pipe that goes from ic to the intake throttle/egr
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09-20-2017, 06:47 AM	#3
mjn77 Lieutenant Colonel 1073 Rep 1,957 Posts Drives: E90 M3 LCI Jerez Black Join Date: Apr 2015 Location: Herts, UK iTrader: (2) Garage List 2011 BMW M3 [0.00]	So maybe just the temperature sensor?
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09-20-2017, 07:13 AM	#5
mjn77 Lieutenant Colonel 1073 Rep 1,957 Posts Drives: E90 M3 LCI Jerez Black Join Date: Apr 2015 Location: Herts, UK iTrader: (2) Garage List 2011 BMW M3 [0.00]	Here are the full error codes..... __________________ // E90 M3 LCI DCT in Jerez Black with Fox Red Leather // Alcantara Trim // ST XTA Coilovers // 1.75 Exhaust Mod // Pinnacle Undertray // @jerez.black.e90.m3 // Euro Alpine Road Trips 2014 2016 2017 2018 2019 2022
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09-20-2017, 07:35 AM	#7
mjn77 Lieutenant Colonel 1073 Rep 1,957 Posts Drives: E90 M3 LCI Jerez Black Join Date: Apr 2015 Location: Herts, UK iTrader: (2) Garage List 2011 BMW M3 [0.00]	As far as i'm aware it's the original battery that came with the car, MY 09/2011. __________________ // E90 M3 LCI DCT in Jerez Black with Fox Red Leather // Alcantara Trim // ST XTA Coilovers // 1.75 Exhaust Mod // Pinnacle Undertray // @jerez.black.e90.m3 // Euro Alpine Road Trips 2014 2016 2017 2018 2019 2022
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09-21-2017, 02:53 AM	#8
Yozh Colonel 870 Rep 2,615 Posts Drives: 2011 335d M-Sport Join Date: Mar 2014 Location: Wet Coast iTrader: (4)	Agree on the battery. But also your MAF is done.
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09-21-2017, 09:13 AM	#9
robnitro Captain 160 Rep 803 Posts Drives: x5 35d e70 2011 Join Date: Sep 2016 Location: NYC area iTrader: (0)	If the engine is running and voltage is low, the alternator is not working properly.
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09-21-2017, 01:05 PM	#11
robnitro Captain 160 Rep 803 Posts Drives: x5 35d e70 2011 Join Date: Sep 2016 Location: NYC area iTrader: (0)	I see engine speed around 660 and 965 in those snap shots with voltages of 11.24 and 12.06v. The battery shouldn't be below 13v with engine running.
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09-21-2017, 01:39 PM	#12
mjn77 Lieutenant Colonel 1073 Rep 1,957 Posts Drives: E90 M3 LCI Jerez Black Join Date: Apr 2015 Location: Herts, UK iTrader: (2) Garage List 2011 BMW M3 [0.00]	Ok, will have the alternator checked as well.
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10-01-2017, 10:49 AM	#14
mjn77 Lieutenant Colonel 1073 Rep 1,957 Posts Drives: E90 M3 LCI Jerez Black Join Date: Apr 2015 Location: Herts, UK iTrader: (2) Garage List 2011 BMW M3 [0.00]	MAF replaced, all error codes cleared. I read that the car will adjust to the new MAF by itself within 30miles/50KM, but i'm fairly sure my MPG is still slightly lower than it should be, but i've not crunched the numbers yet. A quick read online shows that we don't need to reset the MAF adaptations unless there is a note in the box (of the new MAF) that say to do it. __________________ // E90 M3 LCI DCT in Jerez Black with Fox Red Leather // Alcantara Trim // ST XTA Coilovers // 1.75 Exhaust Mod // Pinnacle Undertray // @jerez.black.e90.m3 // Euro Alpine Road Trips 2014 2016 2017 2018 2019 2022
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10-01-2017, 11:37 PM	#15
Yozh Colonel 870 Rep 2,615 Posts Drives: 2011 335d M-Sport Join Date: Mar 2014 Location: Wet Coast iTrader: (4)	BMW says you need to reset MAF adaptations and mean quantity adaptations when a new MAF is fitted. This will also explain your lower mileage.
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