Dependence of the change in the resistance of the temperature sensor of the air entering the engine on temperature
The intake manifold absolute pressure sensor induces a signal from 4 V in the absence of vacuum to 0.5 V in the presence of vacuum.
1. Turn the ignition on, but do not start the engine, and check the voltage from the MAP sensor, which should be approximately 5 V on the red wire.
2. Remove the vacuum hose from the MAP sensor and connect a hand vacuum pump instead.
3. Disconnect the electrical connector from the MAP sensor. Using a voltmeter, check the voltage induced by the MAP sensor on the black/yellow wire. In the absence of a vacuum, the voltage should be approximately 4 V, and when a vacuum is created, it should decrease to 0.5 V.
4. The air intake temperature sensor is located inside the air filter housing. The resistance of the sensor changes depending on the amount of air entering the engine.
5. To check the temperature sensor of the air entering the engine, remove the electrical connector from the sensor, turn on the ignition, but do not start the engine.
6. Measure the voltage at the electrical connector, which should be 5 V.
7. Connect an ohmmeter to the contacts of the temperature sensor of the air entering the engine and measure the resistance of the sensor at various temperatures.