* On the thermostat housing itself: This is the most common location. It's a small sensor, often with a single-wire connector.
* In the cylinder head: Less common, but possible. It would be a threaded sensor screwed directly into the cylinder head.
To locate it definitively:
1. Consult a repair manual: A Chilton's or Haynes repair manual specific to your 1988 Chevy Celebrity will show you a diagram with the exact location. This is the best and most reliable method.
2. Visual inspection: Once you've located the thermostat housing, look closely for a sensor with a single wire connector (or sometimes two, depending on the sensor's function - it's crucial to know which is the coolant temp sensor). The sensor is usually relatively small.
3. Trace the wiring: If you can find the wire from the coolant temperature sensor going to the engine control module (ECM), you can follow the wire to find the sensor.
Remember to let the engine cool completely before working near it to avoid burns.
