Electrical or ground issue?
This may happen a number of times until the temp reaches about 150F. It starts and idles fine but once you give it some juice it can completely drop but not die. Until it gets to the magic 150 F and then it runs perfectly.
I agree with Demonic. It sounds like its choke related. Whether directly or due to issue with too much resistance when the electric choke assist is on.
Electrically. Simple test is disconnect the choke assist. And if its a aftermarket electric only choke, mechanically hold it open.
Better electrical test will be measure the drop in voltage between the alternator output or battery positive and ignition run wire.
Red probe or aligator clip on the highest voltage location.
My pref would be alternator output stud but on harnesses its covered in a boot.
Black probe or aligator clip the battery positive, then the ignition run at the ballast resistor, then the electric choke connector.
Write each of them down. Write down what the ammeter is indicating.
Repeat as the warms up.
This assumes the multimeter can provide a voltage readings as low as 0.1 V
If not then measure voltage to ground at each of the junctions.
For a given current, the bigger the voltage difference indicates a larger resistance in that circuit.
fried a whack of the wiring right up to the bulkhead connector.
Many times the fusible link was located at the bulkhead connector.
If that was melted, replace with a reproduction.
