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Home >> Ford >> 2009 >> Mustang V8-5.4L SC >> Repair and Diagnosis >> Engine, Cooling and Exhaust >> Cooling System >> Engine - Coolant Temperature Sensor/Switch >> Engine Temperature Sensor >> Description and Operation >> Electronic Engine Controls
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Electronic Engine Controls




Electronic Engine Controls

The CHT sensor:

- is mounted into the wall of the cylinder head and is not connected to any coolant passages.
- sends the PCM a signal indicating cylinder head temperature.
- If the temperature exceeds approximately 121°C (250°F) (4.6L [3V] only)/176°C (348°F) (5.4L [4V] only), the PCM disables half of the fuel injectors at a time. The PCM will alternate which fuel injectors are disabled every 32 engine cycles. The cylinders that are not being fuel injected act as air pumps to aid in engine cooling.
- If the temperature exceeds approximately 166°C (330°F) (4.6L [3V] only)/260°C (500°F) (5.4L [4V] only), the PCM disables all of the fuel injectors until the engine temperature drops below approximately 154°C (310°F) (4.6L [3V] only)/164°C (328°F) (5.4L [4V] only).
- The coolant temperature gauge pointer will read fully hot.
- The check gauge warning indicator will illuminate and DTCs are set.
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