My experience with my 2015 MN with surging issues.
The surging started about two years ago and most notably when the cruise control was on and travelling on fairly level roadway with perhaps the slighest of down hill runs. A situation where if not using the cruise one would normally just feather the throttle to maintain speed. Turn the cruise control off and it would drive OK
This surging was intermittent but slowly getting worse when on cruise control.
Fast forward to a recent trip to the noth coast of NSW from the ACT, a 1000 km trip.
Was travelling well with cruise control on until just South of Port Macquarie turnoff when the engine started surging quite badly then the Traction Control light came on and the engine lost power. Fortunately I was able to get into a rest area albeit at a very lesiurely pace. The engine stopped as I pulled up.
Did some cursory checks Oil, Water, was able to manually pump up fuel. No other obvious issues were visible. Tried restarting the engine and it almost started but wouldn't idle.
Then I remembered reading somwhere about repeatedly turning the ignition on and off in quick succession several times , then try starting again.
Yep that worked, the engine started and idled nicely, but I now had the engine light stay on. The traction control light was off.
Drove off and everything was performing nicely, no other warning lights showing so I continue on.
This happened twice more before reaching my destination. The Traction Control light coming on and loss of power, restarted as above.
Contacted a mechanic mate next day who put the scan tool on and it revealled the following codes
P0093 Fuel leak problem (My comment-No obvious leaks identified from tank to Fuel pump)
P0299 Turbocharger underboost
P1299 VGT System (low pressure)
Eventually got to a diesel specialist the next day after the car refused to start no matter what.
Problem was identified in a piece of the wiring harness from which one connector came off the fuel rail pressure sensor. A $20.00 part about 300mm long with three connectors.
Specialist replaced this part and the engine started straight away. They did test drives and further diagnoses which didn't reveal any other issues.
Got my ute back with the engine and cruise control working better than ever.