Symptoms

- Engine Light ON (or Service Engine Soon Warning Light) - Engine rough idle - Engine hesitation

Possible Causes

- Damage harness or connectors - MAP sensor circuit is open or shorted - MAP sensor - PCM or ECM

When Detected

An excessively low or high voltage from the sensor is sent to ECM .

Tech Notes

MAP sensor examples:

Description

The Manifold Absolute Pressure sensor (MAP) provides instantaneous manifold pressure information to the engine's electronic control unit (ECM). The data is used to calculate air density and determine the engine's air mass flow rate, which in turn determines the required fuel metering for optimum combustion (see stoichiometry). A fuel-injected engine may alternately use a MAF (mass air flow) sensor to detect the intake airflow. A typical configuration employs one or the other, but seldom both.