How Does a CHT Sensor Differ from an EGT (Exhaust Gas Temperature) Sensor?

While both CHT (Cylinder Head Temperature) and EGT (Exhaust Gas Temperature) sensors are used to monitor engine temperature, they measure heat in different parts of the engine and serve different diagnostic and tuning purposes.

Cylinder Head Temperature (CHT) Sensors

What it measures:
CHT sensors monitor the temperature of the engine’s cylinder head—typically installed either under the spark plug or in a dedicated bore on the head itself.

Primary purpose:
CHT sensors provide a direct reading of engine operating temperature, helping prevent overheating and head warping, especially in air-cooled engines like those found in aircraft, motorcycles, and some race vehicles.

Key characteristics:

Typically thermocouple or RTD-based
Responds to gradual changes in engine temperature
Valuable for long-term thermal management and reliability
Often used in aviation, motorsports, and industrial engines

Exhaust Gas Temperature (EGT) Sensors

What it measures:
EGT sensors measure the temperature of the exhaust gases as they exit the combustion chamber, usually mounted in the exhaust manifold or header pipe.

Primary purpose:
EGT sensors are used to tune and monitor the air/fuel mixture, turbocharger performance, and combustion efficiency. A spike in EGT can signal lean conditions, misfires, or turbo issues.

Key characteristics:

Almost always thermocouple-based (commonly Type K)
Fast response to combustion temperature changes
Critical for tuning, especially in forced induction or performance applications
Used in motorsports, aviation, diesel performance, and high-performance automotive setups

Side-by-Side Comparison

Feature	CHT Sensor	EGT Sensor
Location	Cylinder head surface	Exhaust manifold or header
Measurement Focus	Engine material temperature	Exhaust gas temperature
Response Time	Slower (material heating)	Faster (direct gas temperature)
Typical Use	Engine health monitoring	Combustion analysis / tuning
Sensor Type	Thermocouple or RTD	Thermocouple (usually Type K)
Applications	Aircraft, motorcycles, race cars	Turbocharged engines, performance tuning

Summary:
CHT sensors measure how hot the engine itself is getting, while EGT sensors measure how hot the combustion gases are after ignition. Both are valuable tools—but for different reasons. If you're monitoring engine health, go with CHT. If you're fine-tuning performance or monitoring turbo conditions, EGT is the sensor of choice.

Still unsure which sensor you need? Contact us and we’ll help you choose the right solution for your application.