Hi Dave,

You said the engine essentially has a delay in throttle response when
cold; and the last cold engine experience was not a delay but rather a
stalled engine.

I would check the fuel pressure 29 psi at Idle 36 Psi at low vacuum.  On
a cold engine the computer assumes the fuel pressure is set and gets no
feedback if the mixture is too lean or to rich.  If the fuel pressure is
low then the engine runs lean and would stay that way until the engine
warmed up, and then the O2 sensor would cause the injector pulse to be
lengthen until the mixture was correct.

Sincerely,

Mark Keller
91 Carat