Vehicle just purchased, and had broke down several times.
Just prior to stopping, it simply lost power and then cut out.
By the time a road service arrived, the engine fired up again and continued to run.

Engine continued to cut out when driven for a short time (approximately 5kms).
When presented on a tow truck, it was able to started up straight away.

Result was a failure within the engine control module, preventing EFI main relay grounding.