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My MPG had dropped into the upper 30s, so over the winter I replaced the plugs and wires hoping that that would get me back to better MPG, it helped.

Had some crappy weather this past weekend figured it was a good time change out the sensor, but as I watched Kirk's clip on youtube he had the 911 machine and it showed a faulty sensor. My question does this fault go away on its own, or is there a reset process?

Thanks
 

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My MPG had dropped into the upper 30s, so over the winter I replaced the plugs and wires hoping that that would get me back to better MPG, it helped.

Had some crappy weather this past weekend figured it was a good time change out the sensor, but as I watched Kirk's clip on youtube he had the 911 machine and it showed a faulty sensor. My question does this fault go away on its own, or is there a reset process?

Thanks
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The SHORT answer:
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No need for a reset. HOWEVER a history trace is kept in memory until a "clear" is done OR until you disconnect the Battery for 20 minutes or more. if you are concerned about forgetting yourself which are old or new faults, you can use the "clear engine faults" menu (menu text might not be this word-for-word, but you get the idea...)

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THE LONG answer:
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When you read any Engine/EFI fault codes with GS911 there are 3 parts to it.
Here is an example:

304: “Oxygen (Lambda) sensor circuit malfunction"
The fault is not present now

Part (1) 304 is the fault code
Part (2) following text is more specific to clarify as the same 304 can sometimes have 2 or 3 different description related to O2 sensor
Part (3) "The fault is not present now" can of course be also "The fault is currently present"

THUS, lets say you go to BMW dealer 1 month after you have change your O2 sensor, unless you had clear all codes, the tech would see that in the past you had an O2 fault but it appear to be fixed (or not currently present). He might just decide to be zealous and install a new O2 sensor again just to be safe (although it clearly said "the fault is not present now")

So it is not black-and-white to clear the codes everytime, if you do your own maintenance and keep following the history yourself, it is not a big issue. Of course after you install the new O2 sensor you would like to 100% sure the fault does not re-appear after a few rides.
 
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