e21 idle correction

["James Barber" <jamesbarber@xxxxxxxxxxxxxxxx>]

I recently inherited a 1983 320i, a wonderful car with new suspension, 
clutch, tires, brakes, etc., but with a few problems which plague me.
    First, the idle speed is extremely high, around 1800 rpm. I adjusted
idle speed at the intake (shown in the Haynes manual) and reduced it to
1600, depending on ambient temperature. Trouble is, it's still high.
Performed basic tuneup, including checking ign. advance, changed plugs,
wires, dist. cap, rotor, oil/air filters and valve adjustment. Mysterious
Bosch ignition trouble? What should I test next?
   Second, when I start the car up on cold days (25F in Ohio) the oil light
stays on and engine sounds like a box of bolts shaken in a can. After
warmup, she purrs like a kitten and runs smoothly, uses about 1Q oil every
oil change (3k miles, Mobil 1 15w-50) Worn out main bearings? Sloppy cam
chain? Nature of the beast? My father had an Isuzu which sounded like
hell-in-a-handbasket on cold days from the time it was new, ran it over 200k
miles with nary a problem. Anyone familiar with this racket? Am I due for an
ungodly main bearing/oil pump replacement? Any input would be greatly
appreciated, since my love of this car far outweighs my economic means to
properly support it, especially if a new motor is in my future. My "other
car" is not fit for Ohio winters-- 1987 BMW R80 {motorcycle!}
Thanks for any advice!
Jim Barber

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