Car won't start after being sat idle for 6 months

[Laughing]

I would seriously doubt it will evaporate in a closed system over winter, it also won’t degrade to no longer ignite injust six months, highly unlikely to be the fuel. I’ve tested fuel sat in old tanks on farms for over 20 years and despite having a lot more sulfur than the regs allow nowadays it still was fine.

You may well be right about the degradation, you would know more than me on that I am sure. It will evaporate though because it is not a truly airtight system. This has happened to me before, though it was a petrol engine that had been sat idle for about 8 months. I think it evaporates through line connectors rather than through the engine as the injectors should be airtight.