O2 Sensor + Manifold switching flap

[Olive]

I need your help concerning a problem of lambda sensors.
I plugged a DIS diagnostic system and understood my problem of "engine light" :

I have 3 problems :
- DME - 0C DME : Oxygen Sensor before cat for Cyl 4-6
- DME - 28 DME : Oxygen Sensor after cat for Cyl 4-6
- DME - 1C DME : Intake manifold switching flap



Concerning the 2 first ones, is somebody able to give me the exact references to order ?
On the BMW ETK, I found only one sensor before cat (ref : 11787831624) and 2 after cat (ref 11787832035 + ref 11781405324). Problem : I can not find which ones are linked to the cylinders 4-6.
So : For cylinder 4-6, could you tell me what are the both exacts references of sensor ? Due to the price, I need to be 100% sure before ordering. 


Concerning the third line, I do not understand well why I have this problem. What is the piece to check ?
I looked the device who turning the flap (ref 7511383) but did not found any trouble with it.
Any idea for this line ?

Thanks for your help :wink:

[NZ_M3]

I have 3 problems :
- DME - 0C DME : Oxygen Sensor before cat for Cyl 4-6
- DME - 28 DME : Oxygen Sensor after cat for Cyl 4-6
- DME - 1C DME : Intake manifold switching flap

Concerning the 2 first ones, is somebody able to give me the exact references to order ?
On the BMW ETK, I found only one sensor before cat (ref : 11787831624) and 2 after cat (ref 11787832035 + ref 11781405324). Problem : I can not find which ones are linked to the cylinders 4-6.
So : For cylinder 4-6, could you tell me what are the both exacts references of sensor ? Due to the price, I need to be 100% sure before ordering. 


Concerning the third line, I do not understand well why I have this problem. What is the piece to check ?
I looked the device who turning the flap (ref 7511383) but did not found any trouble with it.
Any idea for this line ?

Thanks for your help :wink:

Presuming your car is LHD (shouldn't be any different to the RHD model)

before Cat cyl 4-6 - (935mm lambda) - item 2 below part number 11781406622

post Cat cyl 4-6 (750mm lambda) - item 10 below part number 11781405324


The intake manifold switch flap is item 3 in diagram below: part number 11617511383

Use the GT1 to test the flap operation - there's a function in the expert menu to do that (you can open and close the flap on command). It could be an old fault and somebody's replaced the flap but never cleared the codes - when you scroll through to the next screen on the GT1 it should tell you if the fault is present or not - if not, just clear it and check that flap operates (sport mode on - rev in neutral to about 3800rpm and get someone to stand in front of the car to see if the flap opens)

[Olive]

What a perfect answer ! Thanks a lot.

I ordered the both references of sensors this morning and planned to change it next May 17th.

Concerning the flap. I checked during last week end the PN n°6 and did not found any trouble with it. The flap itself is turning well by hand when device #6 is disconect. I will reconnect the DIS and check further.

Thanks again.

[Olive]

@NZ_M3 : I checked the expert mode, on DME, the selection "28" allows to control the intake manifold switching flap. The piece n°6 is turning but only on the right, never on the left => it is only able to close the flap, never open it .
The problem is not indicated as "not present", confirming the problem occurs.

I ordered on EBAY the piece n°6 (actuator). The mechanical system is OK. I can open the flap and close it by hand.

Piece ref is n° 7511383

We will see ... Anyway BMW dealer would not have done more than me on this topic for now. The DIS recommend to change this actuator before anything else.

[NZ_M3]

@NZ_M3 : I checked the expert mode, on DME, the selection "28" allows to control the intake manifold switching flap. The piece n°6 is turning but only on the right, never on the left => it is only able to close the flap, never open it .
The problem is not indicated as "not present", confirming the problem occurs.

I ordered on EBAY the piece n°6 (actuator). The mechanical system is OK. I can open the flap and close it by hand.

Piece ref is n° 7511383

We will see ... Anyway BMW dealer would not have done more than me on this topic for now. The DIS recommend to change this actuator before anything else.

I believe you shouldn't be able to push open the flap when the car is off.

Does sound to me that something is broken inside the switch. Try this - take it off the actual intake - hold the switch in your hand and run the test and see if it turns correctly.

[Olive]

Sorry, I really get some trouble to understood well your advise !
I thought you were talking about an other piece. I found the actuator in this topic :

https://nam3forum.com/forums/forum/csl-register/general/csl-technical-area/519399-airbox-flap-does-not-open

I did not checked this piece !

Regarding the problem met, I guess it is the same thing for me.

Anyway ... for the moment, I removed the flap :thumbs: