I had the call today to say they have found the fault.... exactly like yours, the exhaust valve!!!!!! Mines goons be a few weeks as warranty paper work needs approval and ordering of parts etc. Just glad the fault has been found

might get the garage to look at the exhaust then, it’s been in the garage for over a week now and they still can’t find a fault as the computer isn’t picking anything up, they have said they don’t want to start taking the car apart as could be looking at the wrong thing...... not sure how they expec...

I’m having exactly the same thing on 1.6 2018 allure. Diagnostics are not picking up anything but RAC guy said they need to do a proper test run. Really don’t fancy breaking down again. Anyone had any answers??