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Engine stalling when slowing - test idle control device?

If it runs well cold but poorly warm, it could be a problem with the O2 sensor. Cold, modern engines run in what's called 'open loop', meaning without using any readings from the O2 sensor using standard factory mapping. When warm, the ECU switches to 'closed loop' and starts adjusting air/fuel mixture etc based on among other things the O2 sensor inputs. So when the O2 sensor is faulty, it sends bad data to the ECU, that then in turn causes running problems. Check for fault codes with your Motoscan app or GS911 device.
 
Hi,

The workshop also suggests a reasonable course of action, as poor valve clearance almost always starts with poor engine behavior at idle and low revs. Then it progressively affects the engine's behavior at intermediate engine speeds.
However, this is not the only possible cause. Worn spark plugs do the same thing. Poor engine management does the same thing.

BMW has cleverly equipped its engine management system with a self-learning capability. It is possible that the data memorized and interpreted by the ECU to manage idling may result in incorrect behavior.
Data can be reset using a diagnostic tool. The buffer can also be completely erased, so that the ECU operates as it did when it left the factory.
This is what I'd ask the workshop to do, as it's the easiest way to get started.
 
rod25 said:
I have the same issue after i clean the throttle body or it maybe cleaning the sensor attach on the air intake box. Is that the TPS?
Click to expand...
Hi Rod,
I believe the TPS is attached to the actual throttle body. A sensor attached to the air intake box... Not sure. Some sort of mixture sensor I'd think.




Is it possible a wire from that sensor broke while cleaning?
 

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Hi NZkiwi this is the one im talking abnout i think is this also the temp sensor because it was attach on the airbox as show in the picture below.
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My problem is back. I took it for a ride and it didnt stall, but the idle was high, about 3k RPM. Today the revs during idle were ok, but it stalled after braking. Tomorrow I will call my mechanic.
 
I checked it with motoscan app - only one code: 2767 Oxygen sensor - Signal or value below threshold. It's been there since I bought this bike (with stalling problem).
 
So have you replaced the sensor? Or if it's not the sensor, repaired the wiring or whatever else is causing this fault? Until you do, you have to assume this is most likely causing your issues. Without proper O2 readings the engine will never run right.
 
No. I called workshop today, but they don't have any time right now. I also found a topic on Facebook similar to mine, where it was described that such an error code often appears if the engine stalls, regardless of the cause of the problem. Maybe I will change sensor by myself and check.
 
So my bike is still at workshop. They have changed throttle body sensor - still stalling. I talked to a guy who said that he used to have similar problem. It was throttle body + sensor. If you unscrew the sensor from throttle body you cant adapt/align it again. He bought a used throttle body with sensor, replaced them and no more issues since 2k km. I will try it.
 
Is the oxygen sensor the same as the idle control sensor? If not then check the vacuum lines going to the idle control sensor. Cracks in them will lead to stalling.
 
My stalling problem is gone! I replaced whole throttle body with TPS and 3 yellow relays (with Black non OEM Bosch). Now its working great. No more stalling, revs are smooth and always on the same level.

@edit well, its stalling again :D When its really warm, revs are very low on idle. ECU is rising them very slowly and sometimes it stalls. My next guess is idle valve controler.
 
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I dont think so. I checked it with motoscan and on idle its voltage is between 0.1 and 0.9V so its perfect. I bought new idle Valve motor, do When it arrives I will replace it
 
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