cold start problems

[Steve Ensch]

I have been trying to fix my cold start problem now for several weeks using
the Bentley manual.  I have done everything except 1) checking the fault
codes and 2) adjust CO idle mixture (still factory settings after 170K).

The car is a 1990 90 5cyl 10V, the problem started after some spirited
driving at a road rally and the car sat overnight, weeks later it got
progressively worse.  Now every morning and whenever the car sits for 6-8
hours it will not idle and simply stalls.  Fluttering the pedal just chokes
the engine.  New temp (both) sensors, new fuel, plugs, air filter, 02 sensor
are only months old.  ISV checks out and is clean.  The A/C needs recharging
so I am unable to test if the idle increases as it once did.  Cold start
valve works.  What have I missed.