SureTrack Community Real Fix: Vivaro EGR Recirculating Carbon

Vehicle
2019 Opel/Vauxhall Vivaro 1.6L Diesel

Title
P040000, Replaced Exhaust Gas Recirculation Valve

Complaint
The customer states that the check engine light is on.

Cause
Confirmed customer complaint check engine light on. Connected a scan tool and found code P040000 – Exhaust Gas Recirculation Valve (EGR) “A” flow. Used the scan tool to monitor live data and found the exhaust gas recirculation valve parameter was below specifications. Used the scan tool to repeatedly command the exhaust gas recirculation valve open and closed, monitored the valve position parameters on the scan tool, and found the valve actual position parameter never matched the valve desired position parameter. Disconnected the exhaust gas recirculation valve connector, visually inspected the connector and terminals, and found no obvious signs of damage.

With the key on, engine off, used a multi-meter to check for the presence of voltage and ground at the exhaust gas recirculation valve, and found both were present. Used the multi-meter to measure the resistance of the exhaust gas recirculation valve, and found the measured resistance was within specifications. Removed the exhaust gas recirculation valve, performed a visual inspection of the exhaust gas recirculation valve and found it was clogged with carbon. The results of these tests verified the exhaust gas recirculation valve was faulty.

Correction
Replaced the NOx sensor, cleared codes, performed a road test, and verified that the vehicle operated properly. The check engine light did not illuminate and no fault codes returned.