See Figures 1, 2 and 3
Found on V6, V8 and V10 engines, the intake manifold air temperature sensor is a variable, thermister type which reacts to temperature changes. In cold air, its resistance is high. As temperatures increase, its resistance decreases.
The sensor element itself extends into the intake manifold air stream to provide input voltage to the engine controller. This signal is used along with signals from other sensors by the engine controller to determine the fuel injector pulse width.
This is a test of the sensor only. A complete test of the circuit requires the DRBII scan tool, or equivalent.
- Unplug the wiring harness connector from the intake manifold temperature sensor.
- Using an input impedance volt-ohmmeter, measure across the terminals to test the resistance. The resistance should be less than 1340 ohms with the engine warm. Replace the sensor if not within specifications.
- Test the resistance of the wire harness. Do this between the engine controller wire harness connector terminal 21 and the connector terminal. Also check between terminal 4 to the sensor connector terminal. Repair the wire harness as necessary if the resistance is greater than 1 ohm.
REMOVAL & INSTALLATION
- Remove the air cleaner assembly.
- Unplug the electrical connector at the sensor and unthread the sensor from the manifold.
- Install the sensor on the intake manifold. Tighten it to 20 ft. lbs. (28 Nm).
- Install the electrical connector.
- Install the air cleaner.