Operation CHARM: Car repair manuals for everyone.
Manuals through 2025 now available!

Our trusted friends have launched a new website named LEMON, which has newer manuals. It also contains all the CHARM manuals.

LEMON is the spiritual successor to CHARM, I recommend you try it!

Link: lemon-manuals.la or lemon-manuals.org.ua

(Some people have issue connecting. LEMON is investigating. For now, use Firefox or change your DNS server)

Or, hide this message: temporarily or permanently

Engine Temperature Sensor: Description and Operation






The Cylinder Head Temperature (CHT) sensor:
^ is mounted into the back of the left cylinder head and is not connected to any coolant passages.
^ sends a signal to the powertrain control module indicating the cylinder head temperature.
- If the temperature exceeds approximately 121 °C (260°F), the powertrain control module disables some fuel injectors. The powertrain control module will alternate which fuel injectors are disabled every 24 engine cycles. The cylinders that are not being fuel injected act as air pumps to aid in cooling the engine.
- If the temperature exceeds approximately 166°C (330°F), the powertrain control module disables all of the fuel injectors until the engine temperature drops below approximately 124°C (260°F).
^ DTCs are set.
^ If the engine reaches critical temperature, the following happens:
- The coolant temperature gauge pointer will read fully hot at approximately 121°C (260°F).
- The check gauge warning indicator will illuminate.