Note. For circuit reference, see WIRING DIAGRAMS article.
Circuit Description
Manifold Absolute Pressure (MAP) sensor measures changes in intake manifold pressure (vacuum). A low voltage signal, 2 volts, is sent to PCM on 5-volt reference circuit at closed throttle (high vacuum). A high voltage signal, 4 volts is sent at wide open throttle (low vacuum). DTC will set when MAP sensor intermittently indicates MAP voltage is greater than 4.2 volts.
Conditions for setting this DTC are: no TP sensor DTCs set, engine has been running for predetermined time determined by start-up ECT, TP angle less than 2 percent and engine speed is less than 900 RPM.