The 2020 Ram 2500's Cummins 6.7L diesel uses an EGR valve to recirculate exhaust gases for emissions reduction. When the valve sticks open, rough idle and poor performance result.
EGR System Function
The Exhaust Gas Recirculation system routes a portion of exhaust back to the intake, reducing combustion temperatures and NOx emissions. The EGR valve controls flow rate based on ECU commands.
Symptoms of EGR Stuck Open
Rough Idle
Excessive exhaust gas dilutes the intake charge, causing unstable combustion at idle. You'll feel vibration and see tachometer fluctuation.
Loss of Power
Too much EGR at higher loads reduces oxygen availability, causing power loss and sluggish acceleration.
Black Smoke
The rich running condition from excess EGR can produce visible black smoke during acceleration.
Poor Fuel Economy
Inefficient combustion from improper EGR flow reduces fuel economy noticeably.
Causes of Stuck EGR
Carbon buildup is the primary cause - soot accumulates on the valve and housing, preventing proper closure. Electronic actuator failures also cause stuck conditions.