weird hiccup

[FVEE48@xxxxxxx]

Hello Digesters,
Long time reader, rare contributer here.  
The other day, my wife started our '95 JC chipped 325iA - car has ALWAYS run
exceptionally well, now with 40 K miles.  Anyway, (I was in the garage when
this happened), the car started with a large miss - "humpahumpahumpa"
Startled, I approached the car as she shut it down.  I got in and started it
again - same miss, with the "CHECK ENGINE" light on, as well as the "ASC off"
light on - I cycled the ASC switch to no avail, as the light continued to
shine.   I shut the car  off again.
As we checked the Manual to get the significance of the CHECK ENGINE light (
"get to your Dealer ASAP, your Emissions are screwed up"), a strange SMELL
wafted through the garage. Open door, let smell out, let car sit.  
Contrary to public opinion, the Rule of Let It Sit And It May Fix Itself
sometimes works.  I restarted the car an  hour later - nothing - no miss -  -
perfect.  No lights, no stumbling,  no smell. The car has run perfectly for
days now.
What weirdness took place, here, anyone?
How concerned should I be over this hiccup? ( Wifie is VERY concerned, as she
does the bulk of driving this car).
Norm Borczon
'95 325iA, Sport package, JC chip

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