LEMON Manuals: Even more car manuals for everyone: 1960-2025
Home >> GMC >> 1988 >> Forward Control 5.7 M, Standard >> Repair and Diagnosis >> Engine Performance >> System >> Fuel Injection System - TBI >> Operation >> Coolant Temperature Sensor (Cts)
April 5, 2026: LEMON Manuals is launched! Read the announcement.

Coolant Temperature Sensor (Cts)

The coolant temperature sensor is located in thermostat housing. It is a variable resistor (thermistor) type sensor, and transmits an electrical signal to the ECM proportionate to engine temperature. A low coolant temperature produces a high resistance while a high coolant temperature produces a low resistance.

Coolant temperature is used for fuel management, idle air control, spark timing, EGR operation, canister purge operation and other engine operating functions.