4ks balky when cold

[Tim Paul]

Hello all,

Hoping the collective BTDT brainpower of the list can help me and my 87 4ks.

Here's the scenario:
When the engine is cold (first three minutes or so of running), the car will
accelerate fine up to about 2500 rpm, then the engine will cut out, catch,
cut out, catch a few times. As it begins to warm up a little, the
cutting-out stops, but the power (on acceleration) will go flat and stay
flat until I push in the clutch and rev the motor a couple times (OK, pretty
sure it's not getting enough fuel, here). All this clears up completely
after three or four minutes.

Engine starts and idles fine, hot or cold, and makes plenty of predictable
power once it's warm.

Can anyone point me toward the likely [sensor/switch/wire/widget] culprit?

TIA, Tim

87 4ks -- with all 4 original door handles :-)