[laurentProd]

Hi everyone,
I have searched in the forum for similar problem, but didn't find any useful information. Any help or clue will be really appreciated !

Car:
E93 2008 N43b20 engine (4 cyl europe) with now 35k miles.

Symptoms :
Rough idle when in closed loop and when engine is warming up, sometime stall.
Running really fine in open loop and when warm (after 3 min)

Parts changed:
Rear Nox sensor (grounded)
2 front O2 sensors (car runing rich)
Spark plugs (black, running rich)
1 injector (leaking)
4 Coils (bmw 2013 recall)


The story :
Some months ago, the engine started to run rough at idle when cold or after sitting for some (6) hours.
CEL on dash very frequent when in traffic jam and staying on till a reset by scan tool.
OBDII scan pc ediabas shows : grounded NOx sensor + rich mixture + misfire all cylinders


1. I changed the Nox sensor (summer) which solved the problem (at least the rough idle)...
but the prob came back few month after (4000 miles done).
Car was running rich with CEL on dash.
OBDII scan pc ediabas shows : rich mixture + misfire cylinder 3



2. I decided to changed the spark plugs + coils
--> Didn't work...
OBDII scan pc ediabas shows : rich mixture + misfire cylinder 3



3. Because of the rich mixture, I changed the 2 front O2 sensors (only 2 on this engine).
--> Didn't work...
OBDII scan pc ediabas shows : rich mixture + misfire cylinder 3

4. To solve the misfire (leaky injector??) I changed the injector with a NEW one, latest version.
When unmounting the "old" one, I found that BMW has already changed it with a new version one !! (not the latest but not the old faulty one)
So inspecting the injector I found it very dirty with ?carbon? on it... black residue on the head.
--> Solved the misfire.
OBDII scan pc ediabas shows : rich mixture


After all that work, the car is still running rough at idle when going into closed loop and when cold or after sitting for few hours.
It runs very very fine when cold and open loop and when warm after 3 min of rough idle.
CEL is flashing (rich mixture) very often when warming up.

5. BMW recall on coils didn't changed anything.



Sorry for this long story but I'm trying to give as much details as I can.
Has anyone encountered this kind of problem and solved it?

I really need your help guys. I'm stuck and spend to much money on this issue.
I'm going to give up and trash that car!
What a shame for that overpriced car
My gf fiat 500 is running way much better than mine!!!! WTF????


I'm now thinking of doing the vanos seals. (got the seals already)


HELP!

[laurentProd]

oh.. and no HPFP on this model.

What is the golf tee mod?
What about the carbon build-up in the intake manifold?

[laurentProd]

hum answer to myself.

Not obvious but I think I have a remaining injector leak issue.
Same symptoms but no record in OBDII logs.

I should replace the 3 others... damned it !
How to identify the faulty one with no log?

[DJtoad]

Although I'm not familiar with that engine, I'm assuming the DME needs to be coded with the injector value printed on the side of the new injector. Did you do that when you replaced it? It can be done using INPA.

[laurentProd]

Yup, I've done it!

[laurentProd]

Hum, no one?

[laurentProd]

up!

[Karbon]

Have you checked the intake manifold?

I am not familiar with this engine but I know the 335i's have carbon build up over the years that can cause hesitation and such.

Hopefully you can find out the issue and resolve it cheaply!

[laurentProd]

Thanks "Karbon" (!!! ) for the reply.
No I didn't check. I currently don't have enough room to do it.

I know that small engines like mine are not popular in the US, but here in Europe, it's very common. The engine is the same as the 6 cyl of the 323i.

I try to reset adaptations with inpa but still no luck. (I have already made 1000 miles after the reset)
I didn't try the throttle reset, but I think it's worthless.

[ati80]

Did you ever solve this problem? I have same engine, same problem

[laurentProd]

Hey Ati80 !

I'm living now in Den Haag

Well yeah, months ago now !

just swap the old version of my injectors to newer ones and all probs are now gone!