Good day!!

I am not sure what you have, but it sounds like the fuel pump is not priming the system... It will work when it is cold, but once it heats up and stops, it has trouble getting going again, or the pressure drains out and is not replaced upon the first turn of the key... You could test this theory by turning the key on, off, on, off, on and then start IF you encounter a situation where it won't restart... You have to have the problem present to know the on, off sequence does the job...

It is not the crank sensor... It wouldn't start at all, even with spraying ether in the intake...

The ether replaces the fuel that isn't there... So, that is the problem... Either the pump or the injectors aren't firing for start-up condition...

Let us know what you discover... Good luck!!!

Cheers!!!

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2001 E53 X5 4.4i (03-07-2001 build date) White exterior / hellbeige interior (6MT swap vehicle - Manny)
2002 E53 X5 4.6is (12-20-2001 build date) Imola Red exterior / M-texture interior (Red)
2003 E53 X5 4.4i (06-26-2003 build date) Silver exterior / Black interior (Silvester II)
2008 Mini Cooper S ragtop (04-17-2008 build date) Dark Silver exterior / Gray interior ( Topless)
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