It could be a number of things. The key thing is a shot but I have my 01 X5 4.4 and my buddy has an 04 4.4. We've never swapped out keys. My spare and valet are still in the Medallion bag that came with the car. So 10 years with the same key and I am still good. But might be a fluke. Anyways, is this a 4.4 or 3.0? Also does it have the feature where you turn the key to "Start" and just let go? Meaning does it have the auto crank feature on it? Need a little more info.

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2011 E70 50i M Sport