Intermittent Power Loss & Low RMP Issue - 2013 Freightliner Cascadia

I’m experiencing issues with my 2013 Freightliner Cascadia, including intermittent power loss, inability to rev past 1,000 RPM, possible air restriction, and reduced performance when going uphill. Has anyone encountered similar problems or have any insights on potential causes and solutions?

SPN 411 FAIL 3 Indicates a problem with the Exhaust Gas Recirculation (EGR) differential pressure sensor circuit, specifically a high voltage or circuit failure. This can lead to engine derate and potentially prevent DPF regeneration


SPN 411 FAIL 4 Indicates a problem with the Exhaust Gas Recirculation (EGR) system, specifically a fault with the EGR differential pressure sensor's voltage supply circuit or signal return circuit.


SPN 2631 Indicates a problem with the engine's smoke mode control, likely due to inadequate clean airflow into the engine, potentially leading to a 25% derate


SPN 459520 is an informational code indicating a fault has been detected, potentially related to the exhaust aftertreatment system


SPN 520702 The relay which supplies Fuse group 14 is stuck