Precise analysis
Commands, sensor feedback and related DTCs are reviewed together.
EGR strategy treatment after diagnosis and only within a legally permitted use.
EGR OFF modifies exhaust-gas recirculation control. A faulty valve, restricted circuit or intake problem must first be diagnosed and repaired where the vehicle remains intended for public-road use.
Commands, sensor feedback and related DTCs are reviewed together.
Treatment is not used to conceal an unexplained active fault.
Emission and usage constraints are made explicit.
Diagnose EGR hardware, intake, airflow and related faults.
Confirm the permitted use, then modify relevant strategies coherently.
Review DTC logic, airflow data and post-flash behaviour.