Engine Sensor Descriptions

·      Intake Air Temperature Sensor (IAT)

Adds and removes spark and fuel based on engine temperature.



·      Mass Air Flow Sensor (MAF)

Tells ECM how much air is coming into the intake system and will tell the fuel injectors to deliver 1 pound of fuel for every 14.7 pounds of incoming air. Also is sometimes combined in to the MAF sensor housing.



·      Manifold Absolute Pressure sensor (MAP) 

Measures how much vacuum (or pressure in the case of a turbo) that the intake manifold contains. This sensor is used primarily to enable the ECM to determine the load on the engine. This sensor many times also acts as a BARO sensor which tells the ECM an approximation of elevation.  The ECM will adjust spark timing and fuel delivery based on this sensor.



·      Engine Coolant Temperature Sensor (ECT)

Measures coolant temperature for the ECM which will add timing and fuel when cold and will remove timing and fuel as the temperature increases.



·      Throttle Position Sensor (TPS)

Tells the ECM how much throttle is being requested, it has a range of 0% to 100%. It controls the position of the throttle plate to accelerate or decelerate.



·      Knock Sensor (KS)

Monitors engine detonation and retards the timing accordingly.



·      Oxygen Sensor (O2)

Monitors the end result in the exhaust and is calibrated to feedback that information to the ECM that the mixture is in fact 14.7/1, if not the ECM will adjust the fuel injector pulse width to achieve that mixture.