Exhaust Pressure (EP) Sensor
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The EP sensor is a variable capacitor sensor that is supplied a 5-volt reference signal by the PCM and returns a linear analog voltage signal that indicates pressure. The EP sensor measures the pressure in the LH exhaust manifold. The sensor feedback signal is used for variable geometry turbo (VGT) and exhaust gas recirculation (EGR) valve control.
An open or short in the EP sensor wiring results in an out-of-range low voltage at the PCM.