Fuel Knock — Possible Fault Codes

Found 4 fault codes associated with fuel knock. Codes are sorted by severity — check STOP ENGINE codes first.

⚠️ 2 STOP ENGINE-level codes associated with this symptom. Do not continue driving.

SPN 1077 FMI 14

High Pressure Fuel Rail Pressure

PACCAR MX-13 • Component: High Pressure Fuel Pump / Rail • J1939

🔴 STOP ENGINE

SPN 164 FMI 18

Fuel Rail Pressure critically low

Detroit Diesel DD15 • Component: High Pressure Fuel System • J1939

🔴 STOP ENGINE

SPN 1322 FMI 31

Misfire Detected on Cylinder 6

Cummins ISX15 • Component: Cylinder 6 Injector / Valve Train • J1939

🟡 CHECK AT NEXT STOP

MID 128 SID 1 FMI 5

Injector Cylinder 1 Circuit

Cummins ISX15 • Component: Fuel Injector #1 Solenoid Circuit • J1587

🟡 CHECK AT NEXT STOP

⚠️ 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 knock based on SAE J1939/J1587 fault code definitions and OEM service documentation.