Intermittent starting problem with my Ford B-MAX - what do you think it could be?

I have a 2013 Ford B-MAX Eco 1.0. It's done 52,000 miles and is regularly serviced with Ford parts. However, it has an engine malfunction light on, tick over is irregular and an intermittent starting problem when the engine is warm. Ford dealer is unable to diagnose. What do you suspect?
The first thing to do is to make sure the degas pipe from the turbo to the expansion tank is not leaking.
Answered by Honest John on

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