Question

2003 Ford F250 5.4L V8 with code P1299 engine runs for 5 minutes approx. and shuts down

Answer 1

P1299 Engine over heat condition occured

This is for the cylinder head temperature  (CHT) sensor, beside the sensor how the radiator cooling fan its speed must be sufficient enough to keep the engine at its operating temperature.,  The CHT is not mounted to any coolant passage just the cylinderhead. To access the sensor the intake manifold will need to be removed

Answer 2

P1299 Ford Code - Cylinder Head Temperature Sensor Detected Engine Overheating Condition
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