The typ of miss isn't well described but as they say "99 % of all carby problems are in fact electrical in nature" so I'd be looking at the ignition system first as carbon tracks, failing coil or condenser will all allow the engine to start and idle normally but cut out under load.....

I assume this car has breaker points ignition still , consider Pertronix "Ignitor" breakerless system, no box to fail, it simply replaces the contact points in the distributor, no modification of the car at all .

Please keep us posted, lovely looking car .

__________________
-Nate
1982 240D 408,XXX miles
Ignorance is the mother of suspicion and fear is the father

I did then what I knew how to do ~ now that I know better I do better