[b34thomas]

Hi everyone,

I've got a 2010 3 Series E92 320I SE with a N43 engine (106,000 on the clock). I've had the car for about 18 months and in the past few months (seemingly randomly) on some cold starts the engine light will come on and the engine rattles a bit. I normally pull over, wait a few minutes and restart and it's fine. However, in the last 2/3 weeks the issue has been getting more frequent (nearly every morning now). Still went after restarting every time. Also seems to be burning oil very slowly (indicator was halfway in September, and now in Feb it's just above the minimum).

Took the car into the garage today and they've read various fault codes (I'm not sure which ones however) and have come up with the below plan of action;

Replace Oil Pressure Relief Valve
New Timing Chain
Replace Exhaust Vanos Unit
Replace Denox Sensor

The bill for all the above is coming up around £2k which I don't really want to spend as the car is pretty old anyway. I was just wondering if anyone has had similar issues and if so what was the culprit?

Is it worth just replacing the timing chain for now to see if that fixes the issue and leaving the other bits for a while?
Only want to keep the car going for another 6 months-ish, so trying to avoid anything thats not necessary. Also not sure if a faulty/stretched timing chain could cause error codes in the Denox and Oil Pressure Relief valve?

Any help/guidance would be really appreciated!

[b34thomas]

UPDATE. Here are the fault codes;

8 Faults
2EF7 Map thermostat, activation
30E9 Nitrogen-oxide catalytic converter, ageing
30C1 Engine oil pressure control, static
2A99 Crankshaft - exhaust camshaft, reference
30EA DeNox catalytic converter, sulphurous
2AF4 Nitrogen-oxide sensor, electric
2AF2 Nitrogen-oxide sensor, lambda linear
2AF6 Nitrogen-oxide sensor, lambda binary

[russmw]

Morning,

I have a 2009 320i and at the end of the last year had cold start (sat over night) problems. First thing in the morning it would start but be really rough for the first 30 seconds then sort itself out and run fine, hot\warm starts were 100% fine. The fault was a leaking injector which over night would drip fuel into he cylinder and cause havoc when starting.

You wont get a 'leaking injector' fault code as the car doesn't know its leaking, just the mixtures way out on one of the cylinders and tries to compensate for it which causes more problems until the extra fuel is burnt off and everything resumes to normal. It will create a load of other codes though.

I had some of the codes you're getting but also codes regarding the cylinder mixture (from memory). To figure it out we removed the spark plugs in the morning and tried to start the car - it was obvious which cylinder had loads of fuel in it! new injector is just over £200 and it needs coding to the car.

Mines been 100% since.

Good luck

[Sayek]

Originally Posted by b34thomas

UPDATE. Here are the fault codes;

8 Faults
2EF7 Map thermostat, activation
30E9 Nitrogen-oxide catalytic converter, ageing
30C1 Engine oil pressure control, static
2A99 Crankshaft - exhaust camshaft, reference
30EA DeNox catalytic converter, sulphurous
2AF4 Nitrogen-oxide sensor, electric
2AF2 Nitrogen-oxide sensor, lambda linear
2AF6 Nitrogen-oxide sensor, lambda binary

I say run away from the garage..he is trying to rip you off. Nothing to do with timing chain.


I have owned 2010 N43 about 3.5 years and have experienced the cold start misfire. But you have other issues based on those codes.

I noticed extra oil consumption with the leaking injector. Once the injector was replaced the oil level became stable.

You can pickup new injectors on ebay £160 and its a easy DIY job plus 5 min to code them, i have replaced 3 so far.



30EA DeNox catalytic converter, sulphurous
Too much city driving and Nox build up. Nothing you can do if you drive in city. Needs motorway driving to clear.
This come and goes on my car.


2AF4 Nitrogen-oxide sensor, electric
2AF2 Nitrogen-oxide sensor, lambda linear
2AF6 Nitrogen-oxide sensor, lambda binary
Nox sensor dead. About £400 for the part.


30E9 Nitrogen-oxide catalytic converter, ageing
Nox cat passed its prime and died. About £1500+

But you don't have to replace the Nox sensor and Nox cat for £1950+.

There is an Nox sensor emulator that fits in place of Nox sensor and will trick the ECU and engine works fine. The emulator cost around £330. See many people fit this and no complaints.

[b34thomas]

Thanks both! Really appreciate the advice. The injectors were all changed in September so think its unlikely it's them again...

The car is due for a brake vacuum recall and apparently they sometimes swap out the timing chain if stretched for free whilst doing the fix, so might book it in for that and see what happens. (Even if that's not the cause of this issue, I think it is rattling very slightly so might be worth just doing).

Thanks for the advice re NOX sensor too, will get it fixed soon, are they normally OK to drive for a bit even with these error codes?

[Sayek]

Originally Posted by b34thomas

Thanks both! Really appreciate the advice. The injectors were all changed in September so think its unlikely it's them again...

The car is due for a brake vacuum recall and apparently they sometimes swap out the timing chain if stretched for free whilst doing the fix, so might book it in for that and see what happens. (Even if that's not the cause of this issue, I think it is rattling very slightly so might be worth just doing).

Thanks for the advice re NOX sensor too, will get it fixed soon, are they normally OK to drive for a bit even with these error codes?

The car should be due for 3 recalls.

1. B+ connector to fuse box
2. Brake vacuum pump.
3. Connector for blower motor.

The timing chain is a big job and unlikely BMW will offer a free replacement LOL. Saying that my FRM module was replaced as BMW goodwill during the recall so you never know your luck.

You can drive more than a bit with a broken nox sensor. It just means the would not run in the efficient lean mode.

Bit worrying that all injectors were changed in September and now the leaking injector symptom. Thats the main reason i person replace the injector and not take the word of a garage.


Hope all goes well

[Bmw330]

The new style cam chain tensioners are slightly longer on the n43 now, so if you have a slight rattle the new longer tensioner should sort it

[BimmerBod]

Hi,

Got an engine light on my car.

30EA
2D2A

took it to a couple of garages and one garage mechanic said that you may need to replace the CAT and the DeNOX sensor. Both very expensive - he didnt really want to do the work because he said he did something similar for someone else (replaced both) and the engine light still came on and didn't really want the same job again.

Anyway, took it to another garage and the person agreed with the above but claims he can solve the problem. He said first thing to do is replace the DeNox sensor, he said should solve the problem. If the problem continues the next thing is the CAT.

I dont think it is the CAT because the car picks up speed fine, drives really well and not really sluggish. I've also used two bottles of cataclean just encase it is the CAT and used the expensive unleaded petrol fuel for the past couple of months. I've done all in my power to solve the problem myself...

Anyway got an original nox sensor from BMW today: cost £416 and the garage charging me £150 for labour.... I hope this solves the problem...

I will keep you all updated!

[tauseefquazi]

Any luck guys? BimmerBod, B34thomas

I bought a 318i E91 (Manual) with N43 here in New Zealand. Its a UK import. Currently sitting at 147k kms.

Current codes are very similar to B34thomas.

7 in total

2AF4
2AF2
2AF6
2AF9

Waiting on the denox sensor to arrive to fix the above 4.


30E9. Will clear adaptations after the sensor replacement and see if that fixes the ageing issue.

2EF8 DME: Map thermostat, activation
2A99 DME: Crankshaft - exhaust camshaft, reference

Any idea if the above two are also related to the NOX or would I have to look at something else?

2A99 is causing the check engine light to pop up and a warning on the Idrive saying the power has been reduced, blah blah.

thanks in advance for the help.

[Steve Sas]

Try cleaning the Vanos Solenoids. Use carbi cleaner and make sure you know where the
O ring seal is so it can be returned correctly. Sometimes fixes the issue.
You can even use 12v supply to pulsate while submerged in solvent. But keep sparks away as it will ignite(happened to me)

2EF8 code isn't important. its a small heater inside thermostat.