The exhaust gas recirculation (EGR) system helps minimize nitrogen oxide gases coming from your vehicle’s exhaust. The ECM/PCM detects an open circuit condition of an EGR motor control circuit for greater than 3 seconds.

What repairs can fix the P0403 code?

1. Replacing the shorted or open EGR vacuum solenoid.
2. Replacing a corroded connector to the EGR vacuum control solenoid.
3. Repairing the wiring shorted to the EGR vacuum control solenoid.

Some symptoms of a faulty solenoid include poor idle, poor acceleration, stalling, low engine vacuum and hesitation or rough riding while driving.

If the EGR solenoid fails it can disable the EGR system from recirculating exhaust gases. For certain engines this can cause a large increase in cylinder and exhaust gas temperatures. Excessively high cylinder temperatures can cause engine ping and knock, which can lead to serious engine damage if left unattended.

Vacuum solenoid valves, also known as Electro-pneumatic pressure converters, Electric switch over valves or Boost control solenoids are used to control many systems of engines by controlling actuators – for example, variable geometry of the turbocharger, EGR valves, various bypass or throttle valves etc.

P0443 is an OBD-II generic code that the engine control module (ECM) has detected a malfunction with the purge control valve or its control circuit. This could mean an open or short in the valve or circuit.

What the P0402 code means. P0402 is an OBD-II generic code that the engine control module (ECM) has detected indicating the engine exhaust gas recirculation ( EGR ) valve is flowing too much recirculated exhaust gases when it is commanded to open the flow of gases into the intake manifold.

The P0403 code represents a problem with the Exhaust Gas Recirculation Solenoid or circuit. Below is the chart that explians and directs us to where the problem may exist.

P0443 is a very common OBD2 code. It’s generic, which means that it has the same meaning for the Ford Expedition as it would for any other vehicle. If your Expedition has this code, it is indicating the EVAP purge control valve circuit is malfunctioning..