Possible causes
– EGR volume control valve stuck open or closed
– Faulty EGR volume control solenoid valve
– EGR volume control solenoid valve harness is open or shorted
– EGR volume control solenoid valve circuit poor electrical connection
– EGR temperature sensor and circuit
– Faulty EGR volume control solenoid valve
– EGR volume control solenoid valve harness is open or shorted
– EGR volume control solenoid valve circuit poor electrical connection
– EGR temperature sensor and circuit
When is the obd code mean?
An improper voltage signal is sent to Powertrain Control Module (PCM) through the valve
Symptoms
– Engine Light ON (or Service Engine Soon Warning Light)
– Possible engine hesitation
– Possible engine hesitation
P0403 GMC OBD Code Description