★ ENGINE TECH · ALL MODERN DIESEL + MANY GAS ENGINES

Diesel EGR (Exhaust Gas Recirculation) + California Smog

QUICK ANSWER

EGR recirculates exhaust gases back into the engine to reduce NOx emissions. Critical for diesel smog passage — deleted EGR causes immediate California smog failure (visual inspection catches missing components).

Common EGR (Exhaust Gas Recirculation) smog issues

EGR cooler clogging (common on 6.7L Cummins), EGR valve sticking open, deleted EGR system

How to fix

EGR cooler replacement, valve cleaning/replacement, OEM emissions restoration if deleted

Typical repair cost

$200-$2,000+

Common questions

What is EGR (Exhaust Gas Recirculation)?

EGR recirculates exhaust gases back into the engine to reduce NOx emissions. Critical for diesel smog passage — deleted EGR causes immediate California smog failure (visual inspection catches missing components).

What causes a EGR (Exhaust Gas Recirculation) smog failure?

EGR cooler clogging (common on 6.7L Cummins), EGR valve sticking open, deleted EGR system

How is EGR (Exhaust Gas Recirculation) fixed?

EGR cooler replacement, valve cleaning/replacement, OEM emissions restoration if deleted

What does fixing cost?

$200-$2,000+