Hello and Welcome -
My name is***** happy to help / advise.
You say that they say they cleared the fault codes and say its fine. Evidently its not fine - and whats more , there wouldn't likely have been any fault codes if the EML doesn't come on while driving.
With such an intermittent fault , honestly, such can be hard to diagnose so its best to start at the start.
What is the vehicle service history like - while its got such low mileage, it still has to be serviced "time" wise on schedule -so if thats not happened - it would be a good idea to have at least an engine service done - which would inc the change of oil -and filters. Often this will pick up and cure such a fault.
If the servicing is ok - then I suggest strongly to double check the condition of the air filter - regardless of service history ( sometimes they get missed! ).. and change if dirty.
Then - in any event, have the fuel filter changed - as this is very likely your issue. At the same time - put in the tank a good , well known Diesel fuel injection system cleaner -from any good car shop - preferably one called Forte... Too - use a well known / good make of filter - such as Mahle - Mann etc or genuine Ford.
To be honest - you may well find that cures this issue you have altogther. - IF not, then the EGR valve is suspect and should be removed for test and cleaning... Often they will respond to cleaning - but be sure the port where it fits is thoroughly cleaned at the same time.
Working as above through , should see this issue fixed for you Dan.
Let me know how you go..and / or let me know if you need anything further on this..
~>>~~>>~ Meanwhile now at this point- Please do click on the "Exc / Ok rating" for me at this time.. "Thank you" in advance for that .
.. Note that you can get back to me anytime at all after doing the rating - it doesn't close you out --
Best Rgds, MIKE