Strange sound from M20 distributor

["Will Hartje" <WHartje@xxxxxxxxxxx>]

I have a strange sound coming from (I think) the distributor on my 1990 325i
. It only occurs first thing in the morning and only for about one minute
during which time it slowly diminishes away to nothing. It sounds like there
is gravel in there, being churned round by the rotor.
This only occurs with a stone cold engine.
After a minute everything sounds fine, anybody else had this experience?
TIA for any suggestions
Will Hartje

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