Lincoln Repair Questions? Ask a Mechanic for Answers ASAP
Did the mechanic verify the valve timing? this engine has cam shaft phasers that change the valve timing and they can fail and cause one bank or cylinder head to have misfires. With the dealerships diagnostic tool(IDS) they can watch cam timing advance and compare each side. usually with your symptom you will see a big difference on the side not firing right. It is also possible the chain jumped. Let me know how many miles and if the engine makes any noises.
The 5.4L 3 valve engines use oil pressure to operate the VVT(variable valve timing) system. poor maintenance can effect the operation and things just fail with mileage. They do not always set codes when issues like this happen. Most common cause would be a bad phaser, not that bad to do or not too expensive. Let me know what you find . You can tell the shop to check the actual and desired bank 1 and 2 valve timing on the IDS.
after market is much cheaper than ford/Lincoln.
wow! not too many last that long. Must be highway miles. Have you replaced the phasers, chains or tensioners?
you must do regular oil changes, that is the key for this engine.
All I can say is wow. highway helps , best for an engine.
if the vehicle is still in the shop let me know what they find. I use a phone APP that shows live data like this. Torque pro from google play. I use it on my phone with an OBD2 Bluetooth adapter. less than 40$ for both.