The coolant temperature sensor (CTS) on a 2002 Chevrolet Impala with a 3.4L engine is typically located on the
engine block, near the thermostat housing. It's often a single-wire sensor, and it might be a bit difficult to see without removing some components. You'll likely need to consult a repair manual specific to your vehicle's year and engine to get a precise location and visual aid. A Chilton's or Haynes manual will be helpful.
Important Note: There might be *two* coolant temperature sensors; one for the gauge and another for the PCM (Powertrain Control Module). The location of the one for the PCM is crucial for accurate engine operation. A repair manual will help you distinguish between them if there are two.
