Chart C1D - Map Output Check (All Engines)
The MAP sensor measures manifold pressure (vacuum) and sends that signal to the ECM. The MAP sensor is mainly used for fuel calculation, when the ECM is running in the throttle body back-up mode. The MAP sensor is also used to determine the barometric vacuum to the sensor. The change in voltage should be instantaneous. A slow voltage change indicates a faulty sensor. Check vacuum hose to sensor for leaking or restriction. Be sure no other vacuum devices are connected to the MAP hose.