Refine G4JS Engine Coolant Temperature Sensor 39220-38020

If your Geely G4JS engine shows cold-start difficulties, rough idle, elevated fuel consumption, or gauge temperature needle not rising with cooling fan frequent activation, the coolant temperature sensor may be aging. This sensor monitors coolant temperature in real time and transmits to the ECU to control injection quantity and ignition timing for stable operation across temperatures. OEM 39220-38020; fits Geely G4JS. Install with sealant on threads and torque to spec to avoid coolant leakage or signal distortion.