Intake Air Temperature Sensor Wiring.  The engine temperature sensor is essentially a resistor which changes value according to the temperature of the engine.  Technically, this is called a thermister.  The intake air temperature sensor informs the SMC of the temperature of the incoming air-charge so that the SMC can provide offset fuel and/or ignition timing to prevent engine damage due to high intake temperatures.  The sensor has a single electrical connector utilizing two wires which can be connected to the SMC pins 30 and 17 without concern for polarity.  For proper operation, it must be mounted in the stream of air between the intercooler and the engine.

The short brass sensor you see in these photos report air temp to the Autronic SMC.  It uses standard 1/8" pipe thread.  The longer probe is a thermocouple for my digital IC temp gauges.

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