Possible Causes
NOTE: The listed causes may not be a complete list of all potential issues and there may be other causes.
- Faulty Exhaust Gas Recirculation (EGR) Throttle Position Actuator (EGRTP)
- EGRTP actuator wiring harness open or short circuit
- Poor electrical connection in EGRTP actuator circuit
- Faulty Powertrain Control Module (PCM)
Description
The Exhaust Gas Recirculation (EGR) Throttle Position Actuator (EGRTP) modifies airflow into the intake manifold by controlling a throttle plate inside the throttle body. A Pulse Width Modulated (PWM) signal from the Powertrain Control Module (PCM) is used to control the rotational movement of the EGRTP actuator. The throttle plate position is determined by an input signal from the EGR Throttle Position Sensor (EGRTP). The EGRTP sensor is a rotary position sensor. A 5-volt reference voltage supplied by the PCM is used by the sensor to provide an input signal proportional to the throttle plate angle. The Diagnostic Trouble Code (DTC) is set when the EGR throttle closed position voltage is below 3.83 volts or when the EGR throttle open position is above 0.93 volts during initial power-up.