That’s what I’d like to know. That’s what is concerning is that a few posts early on mention CHT to be normal up to 220* but I’m seeing greater than 240*... I know this isn’t the same as coolant temp , I was making it clear that the vehicle wasn’t overheating or popping any CEL’s. I just don’t know the how it’s obtaining that measurement or from where. Hoping someone here might be able to explain
Nothing to be concerned about. The CHT is literally measuring the temperature of the cylinder head itself, not the coolant, which is why it will read significantly higher than ECT under a variety of conditions. The CHT sensor is located on the rear of the passenger side cylinder head, below the CMP sensors.
The purpose of the CHT is to prevent an engine overheat condition in the event that a significant loss of coolant occurs. Once the ECT is no longer surrounded by coolant, the readings will not be accurate. This causes ECT to drop while actual engine temperature is increasing. As the CHT is reading the cylinder head temp and not coolant temp, the readings will remain accurate and the PCM will know you enter limp mode/fail safe strategy.