This is the typical symptom of a bum fuel pump. You get a non start when the pump lands on a dead commutator bar.

Random wiggles cause it to move just enough to get to a good spot and it will fire up.

I teach the method of starting of turning the key to the “on” position and wait for the fuel pump hum to stop before cranking. It takes less than six seconds.

If you don’t hear the hum, pump isn’t working. Listen close, Turn the fan down to lowest spot to learn what to listen for.

You can also test the fuel pressure at the fuel rail under the plastic noise shield under the hood.

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