Turbo

MAT Sensor:

The Manifold Air Temperature (MAT) Sensor, located on the intake manifold near the idle air control valve, is a thermistor (resistor) whose resistance value varies in relation to the temperature of air entering the engine. Low temperature results in high resistance while high temperature results in low resistance.

The ECM supplies a reference signal (4 - 6V) to the sensor and by measuring the voltage change can determine the manifold air temperature. This input is used in ECM calculations of injector pulse width ("ON" time).

Temperature (°C/°F) Resistance

0 / 32 9.4K ohms
20 / 68 3.5K ohms
40 / 104 1.5K ohms
60 / 140 667 ohms
80 / 176 332 ohms
100 / 212 176 ohms