GM Caprice 1990-1993 Repair Guide

Manifold or Intake Air Temperature (MAT/IAT) Sensor

Print

See Figure 1



Click image to see an enlarged view

Fig. Fig. 1: Manifold Air Temperature (MAT) sensor - 1990-91 vehicles except 5.0L (VIN Y) engine

OPERATION



The MAT or IAT sensor is a thermistor which supplies manifold air temperature information to the ECM. The MAT sensor produces high resistance (100,000 ohms at -40°F/-40°C) at low temperatures and low resistance (70 ohms at 226°F/130°C) at high temperatures. The ECM supplies a 5 volt signal to the MAT sensor and measures MAT sensor output voltage. The voltage signal will be low when the air is cold and high when the air is hot.

REMOVAL & INSTALLATION



  1. Disconnect the negative battery cable.
  2.  
  3. Disconnect the sensor electrical connector locking tab.
  4.  
  5. Remove the sensor.
  6.  

To install:
  1. Install the sensor.
  2.  
  3. Connect the electrical connector.
  4.  
  5. Connect the negative battery cable.
  6.  

 
label.common.footer.alt.autozoneLogo