Z31 (CHTS) CYLINDER HEAD TEMPERATURE SENSOR
Overview
The Cylinder Head Temperature Sensor (CHTS) is built into the cylinder head and monitors temperature changes, sending a signal to the ECU.
How It Works
The sensor uses a thermistor—a resistor sensitive to temperature. As cylinder head temperature rises, the electrical resistance of the thermistor decreases.
*WARNING* - Do this modification at your own risk. We Are not responsable for any issues of your own doing.
Part Numbers
| Part Number | Description |
|---|---|
| 22630-01P01 | (CHTS) Cylinder Head Temperature Sensor |
| 24079-01P00 | Cylinder Head Temperature Sensor Sub-Harness |
Common Problems
- Missing or backfiring on cold starts. ECU Code #13
- Fouling out plugs (rich)
- Black smoke
Troubleshooting
To test, measure the Ohms across the 16 pin ECU connector on terminals 23 and 26. The chart will provide the correct readouts:
| Cylinder Head Temperature | Resistance in Ohms |
|---|---|
| Above 20°C (68°F) | Below 2.9kΩ |
| Below 20°C (68°F) | Above 2.1kΩ |
If the readings are OK here, then replace the ECU. If the readings are out of spec, first check the harness for damage including corrosion and broken wires.
If the harness looks OK, then you can test the sensor using the chart below.
