This sounds like good stuff and you know what you are talking about.

It is only when put in gear so could there be a problem with the gearbox or the drive train causing the eng to stall. Like a failed free wheel on a bike would cause the pedald (eng) to react to the drive train?

Also inj/choke sort a problems where the car is just not reacting to the extra load came to mind and when warm, perpetual feed stops the problem?

Thanks for the docs.