Pressure sensors

Mainfold Absolute Pressure (MAP) Sensor

The manifold absolute pressure sensor is a variable resistor used to monitor the difference in pressure between the intake manifold at outside atmosphere.

This information is used by the engine computer to monitor engine load (vacuum drops when the engine is under load or at wide open throttle). When the engine is under load, the computer may alter spark timing and the fuel mixture to improve performance and emissions.

Knock sensor

Engine knock is characteristic of an uncontrolled combustion process and can cause engine damage. That is prevented by a knock sensor, a noise sensor near the engine.

The Knock Sensor is a Piezo Electric device that when you stress it, a voltage is produced. It senses knock and transmits information to the electronic engine management control unit. This influences process control in the engine, for example timing and fuel injection until knock is eliminated.

Knock is frequently caused by fuel that does not comply with the required minimum quality.