[m_star01]

Hello all, I had the EML come on and it's now been in the garages for diagnostics. Various, garages said I need a new NOX sensor, timing chain, thermostat etc etc. So i got a mate to get his car diagnostic reader to run the codes for me so i can see what is going on.

What do you guys think? This is the full error list:

• 2E8E - intelligent battery sensor, communication
• 30C1 - Engine oil pressure control, static
• 2EAE - no message from nitrogen-oxygen sensor 1
• 30DC - nitrogen-oxygen sensor, heating
• 2EF7 - Map thermostat activation
• 30EA - DeNox catalytic converter, sulphurized

My car is a E90 2010, 320i N43. Most driving is short journeys. Anyone help me how should i tackle the issues i am having? as i have spent hundreds at different garages who diagnosing and telling me different things.

[therealdb1]

Are these historic or current codes?
Are there any symptoms apart from the EML being illuminated?
What are all these garages doing about your issues or are you only asking them to carry out a diagnostic check?

Could be several issues all at once with the unrelated codes.

Now you have the list I would clear the error codes and see what comes back immediately and deal with that.

There's obviously something about the NOx sensor that the car doesn't like and it is best to check the actual engine temperature to help determine if the thermostat is working. You might need an oil pressure sensor too who knows at this point but you need to adopt a logical approach rather than random swapping out which shall be expensive and not guaranteed to cure the problem.

[m_star01]

Hi mate,

Yes these was on car for 3 weeks. I have now cleared all those faults as you suggested. Is there any which are major concern if they come again? All garages have told me NOX sensor based on codes is the culprit. But some going as far as saying new timing change etc.

So I thought I ask see what you guys think if those errors all related to nox sensor or isolated cases of parts failed or failing.

[therealdb1]

See what codes come back but a new NOx sensor isn't the end of the world.
It's a bit early to be talking about timing chains which would be something expensive unless you can DIY!
If you intend keeping the car it might be worth investing in your own code reader as it will soon pay for itself but get a BMW specific one and not a cheap generic one. Companies such as Foxwell do them or you can get Apps like Carly or my personal favourite is INPA/ISTA but you need a laptop for the last one although the software is available for free from several sources you just require a lead to connect car to computer.

[m_star01]

I cleared faults last night. did 2 drives today; 1) 3 miles cold start in morning, 2) 4 mile journey.
The EML came on and this time the following errors came up only:

2E8E - intelligent battery sensor, communication
2EAE - no message from nitrogen-oxygen sensor 1
30DC - nitrogen-oxygen sensor, heating
2EF7 - Map thermostat activation
30EA - DeNox catalytic converter, sulphurized

I am still thinking NOX sensor is at fault however i did replace this last year. Anyone know what "Map Thermostat" is??

[therealdb1]

Was the NOx sensor you fitted an OEM one? These cars are very fussy in general when it comes to sensors and can spit the dummy if you dare fit after market sensors.
But also manufactured goods do fail sometimes so perhaps you have been unlucky and your new one has gone rogue for whatever reason.

2EF7 suggests that your electronically controlled thermostat is not working correctly. It's unlikely to be the DME itself but it could be the connection from that to the thermostat or the thermostat itself. It depends how much diagnostic digging you wish to do before swapping out the thermostat or you could just go in with a new one.

The IBS fault again is either a poor connection around the sensor or the sensor itself. You should be able to check the connections relatively easily.

Deal with one problem at a time is best!

[m_star01]

Yes it was a after market one not original. I'm tempted to maybe fit a used genuine bmw one just to see if this rectifies rhe issue.

Also what's rhe correct part name for the "electronically controlled thermostat"? That is causing error 2EF7? I can check part number and see if its cheap or not.

THE Ibs I leave till the end as I'm sure that does cause the EML ??

[therealdb1]

I believe it is just called a thermostat!
It'll be the one next to the waterpump if you look on Real OEM for the part number.

Depends how much a second hand NOx sensor is compared to a new one but if it is only a few quid it is worth a try provided, of course, that the second hand one is guaranteed working!

IBS is the least of your problems at the moment you can deal with that later.

[F31B48]

I think you should replace the thermostat as well. If the engine isn't getting up to operating temperature it will be using too much fuel and not running at it's optimum.

[m_star01]

Originally Posted by EvaBmw

I think you should replace the thermostat as well. If the engine isn't getting up to operating temperature it will be using too much fuel and not running at it's optimum.

Thanks i definitely take your advice. Is replacing the engine thermostat a quick job or i am looking a big bill from a garage? I also understand there is a housing as well.

Just looked on realOEM and this item has no fancy name but i am sure this is the correct part?

https://www.realoem.com/bmw/en/part?...&q=11538671515


https://www.onlinecarparts.co.uk/mah...l-7768571.html

[F31B48]

Yes that's it. It's not too difficult to replace, but it is in an awkward spot. You may have to access it from underneath. If you're going to be working on this car yourself It's probably a good idea to download ISTA, which is the BMW diagnostic software. It has all the repair instructions integrated in it, so you can follow the guide in there. It also has all wiring diagrams and guided diagnostic troubleshooting as well. You can download it in the BMW coding section of this forum. I think the thread is called "software....help yourself"

[0l0dom0l0]

Your new nox sensor is faulty. Replace it and register a new sensor.

You'll also need to do a long run and request a catalyst desulphurization.

[m_star01]

Thanks mate. Btw how do you register a new NOX sensor? I'm not sure my garage mentioned this is there a terminology i should tell them which they understand why its needed? As all they said was fit, reset codes and done.

[0l0dom0l0]

You would be best taking the car to a specialist.

https://bimmerprofs.com/encoding-new-nox-sensor/