2015 ford transit tipper intermittent starting problem

[HamishMcmood]

Hi 2015 2.2 ford transit tipper double cab

When I turn the key check engine comes up and the van will turn over strong but not start

If I wait 2 mins 40 seconds (as long as it take for the electrical whine sound from the engine to stop) it starts up perfectly and runs fine until the next time which is every time I leave it for a 15 mins or more.

Has been happening for a week or so van is in daily use no other problems.

Have tried disconnecting the batteries for an hour or so.

My cheapo fault code finder is finding no codes

Have tried googling but it's quite a specific problem regarding the 2mins 40 and I don't know what that whine actually comes from. Hoping for some help from a more mechanically minded member.

[HamishMcmood]

2015 2.2 ford transit tipper
if I put the key in and turn it check engine comes on, the van turns over strong but won't start.

If I wait 2mins 40 seconds after that (when the high pitch buzz from the engine bay stops) it turns over fine and starts no problem and everything works fine.

Until the next time I start it (15 plus minutes not being driven). Been like this for a week.

Hopefully somone know a fix and what that noise actually is if anyone want to hear the noise somone else has uploaded it to YouTube but no one has come forward with a explanation of what it is will add link on next post if forum rules allow