too rich!

["Toby Smith" <tobys@xxxxxxxxxxxxx>]

halfway to work each day my 325es starts to sputter and choke - black
smoke indicates way too rich a fuel mixture.
is there anything in the emissions controls that would make such a
drastic adjustment to mixture?
i always fiddle around with this and that, but it seems like time is
what gets the problem to reset (about 5 or 10 minutes).
just did a tune up (plugs, air & fuel filters, coolant temp sensor,
etc)the car runs very smoothly, but then this happens every so often.
can the 02 sensor make such a drastic change?


- -Toby

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