<E36> Cold start problem

[Jason Surprise <jmsurpri@xxxxxxxxxxxxxxxx>]

I have a peculiar cold start problem that has been there since I bought
the car (94 325i) two years ago.  Actually I'm not even sure it's a
problem since I've never seen it do anything different.  I figured I'd
ask and find out.  

In all other cars I've been in, when cold starting the car after it's
been sitting overnight or for a long time, the car will initially rev
higher than idle (say 1500rpm) until the car warms up.  I guess it's an
automatic choke or something to that effect.  Ever since I bought my
car, it does not do this.  After I start, the idle drops immediately
to 600-700rpm.  Other than this oddity, there's no other apparent
problems, it doesn't idle lower than idle, it doesn't buckle or try to
stall.  Under extreme temperatures, close to or below freezing, I have
seen it idle higher than normal at ~900rpm, but that still isn't close
to what I've seen in other cars.  

Is this something that I should be worried about?  Any recommendations
on how to fix?

Thanks for your help!
Jason

94 325i

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