you are extremely lucky. this is a notorious problem with those engines. usually they'll get sucked into the return and destroy your motor. you were lucky. everybody who purchases an E38 should drop their oilpan and check the oil pump bolts, and torque them to spec. I checked mine as soon as i bought the car when i changed the oil and they we're only hand tight. anyway, good luck with the new car, and visit e38.org for more info on this problem and a torque diagram.
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