Manifold Air Temperature (Mat) Sensor
If a MAT sensor-related code is present, see appropriate G - TESTS W/ CODES article. An out-of-calibration sensor may not set a trouble code. Use following procedure to test calibration. Disconnect MAT sensor harness connector. Connect ohmmeter between sensor terminals. Sensor resistance should be as specified. See MAT SENSOR RESISTANCE . With vehicle sitting overnight, MAT sensor and coolant sensor should have close to the same resistance reading.
MAT SENSOR RESISTANCE
| Temperature °F (°C) | Resistance (Ohms) |
|---|---|
| 210 (100) | 185 |
| 160 (70) | 450 |
| 100 (38) | 1800 |
| 70 (20) | 3400 |
| 40 (4) | 7500 |
| 20 (-7) | 13,500 |
| 0 (-18) | 25,000 |
| -40 (-40) | 100,700 |