DTC P1128: Manifold Absolute Pressure (Map) Sensor Lower Than Expected

Turn ignition on. Check MAP sensor using scan tool. If 16.0 in. Hg or more, or 1.61 volts or more is indicated, problem is intermittent. System is okay at this time. If 16.0 in. Hg or more, or 1.61 volts or more is not indicated, replace MAP sensor.