If you are getting air gap code I would bet the computer though able to extract the correct wheel speed that based on the actual waveform knows that the sensor is at the wrong distance to the sensor ring in the wheel bearing.

If you know which wheel, I would work on some small adjustments to the position of the sensor before replacing e g. Shim the sensor out or sand off a little of the plastic so you can install farther in. First I would clean out the mounting hole with a wood rod and sandpaper then if the sensor isn't tight, wrap it with Teflon tape. There's a recent thread where somebody had nearly the same problem and just some Teflon tape solved the problem.

The sensors are stupid sensitive! A coating of rust on them is enough to through them off so clean them also. Lastly ensure the angle is perfect. There is very little tolerance to the mounting hole but if it's not straight out could cause the air gap alert.

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2011 E70 • N55 (me)
2012 E70 • N63 (wife)