[rich]

This may not be much help, but next time it happens check to see you have spark. You could have a bad ignition switch. It happened to me on my 84 533IA. It started as an intermitted problem. engine would crank but not fire. Just a thought. The ICV could be sticking from age. remove and spray it with carb cleaner. I had this happen also. The car kinda galloped at an idle but still ran OK. If it was only happening when cold I'd say stuck cold start valve. Good Luck