Fuel Consumption Increase — Possible Fault Codes

Found 3 fault codes associated with fuel consumption increase. Codes are sorted by severity — check STOP ENGINE codes first.

SPN 520605 FMI 7

SCR System Mechanical Malfunction

Detroit Diesel DD15 • Component: SCR Catalyst / NOx Sensors • J1939

🟡 CHECK AT NEXT STOP

MID 128 PSID 90 FMI 4

EGR Differential Pressure Sensor

Volvo D13 • Component: EGR Differential Pressure Sensor / EGR Valve • J1587

🟠 CHECK SOON

SPN 107 FMI 16

Air Filter Restriction excessive

Volvo D13 • Component: Air Filter / Air Intake System • J1939

🟠 CHECK SOON

⚠️ Diagnostic Note: Symptoms can have multiple root causes. Always verify with a diagnostic scan tool before replacing parts. The fault codes listed above are possible matches for fuel consumption increase based on SAE J1939/J1587 fault code definitions and OEM service documentation.