1997 Expedition 5.4L Cylinder Head Temperature Sensor:
- Is mounted into the wall of the cylinder head and is not connected to any coolant passages.
- Sends a signal to the PCM indicating the cylinder head temperature.
- If the temperature exceeds 130°C (265°F), the PCM disables four fuel injectors at a time. The PCM will alternate which four injectors are disabled every 32 engine cycles. The four cylinders that are not being fuel injected act as air pumps to aid in cooling the engine.
- If the temperature exceeds 166°C (330°F), the PCM disables all of the fuel injectors until the engine temperature drops below 154°C (310°F).
- DTCs are set.
- If the engine reaches critical temperature, the following happens:
- The coolant temperature gauge pointer will read fully hot at 121°C (250°F).
- The check gauge warning indicator will illuminate.
Download : 1997 Ford Expedition Cylinder Head Temperature CHT Sensor
Download : 1997 Ford Expedition Parts and Accessories