Cummins ISB CM850 (2003-06) Fault Code: 1718 PID: SPN: 1322 FMI: 11 Engine Misfire for Multiple Cylinders ? Condition Exists. Engine misfire has been detected in multiple cylinder numbers.

Posted by PerDiezel Solutions on January 18, 2026

If Fault Code 1718 is inactive in the ECM memory and there is no complaint such as ?low power? or ?engine misfire?, it is possible that an intermittent event such as air entering the fuel system following a filter change caused the fault. Inactive counts of Fault Code 1718 should be disregarded unless other performance symptoms are present. The engine coolant temperature must be greater than 160?F before this diagnostic will run.

Causes of cylinder misfire can include:

1)Valve lash out of specification (compare actual valve lash to reset limits)
2)Cylinder failure (check for high blowby when the engine is loaded)
3)Valve failure or valve held open (listen for intake valve ?chirping? noise in the intake)
4)Cylinder head or gasket failure (look for signs of oil, coolant, or casting flash in the intake or exhaust passages)
5)Extreme camshaft wear (inspect the camshaft lobes for wear)
6)Extra, missing, or damaged sealing washer under an injector
7)Injector failures (?swap? injectors to see if the problem ?follows? the indicated injector).

On-Board Diagnostic (OBD) Information:

1)The ECM illuminates the malfunction indicator lamp (MIL) when the diagnostic runs and fails
2)The ECM turns OFF the malfunction indicator lamp (MIL) after 3 consecutive ignition cycles that the diagnostic runs and does not fail. The MIL lamp and fault code can also be cleared using the INSITE? service tool
3)The fault code will be cleared from the memory after 40 consecutive drive cycles when the diagnostic runs and passes.

Possible repairs:

1)A damaged injector has been detected. Replace the injector.

Cummins ISB CM850 (2003-06) Fault Code: 1717 PID: SPN: 3241 FMI: 15 Exhaust Gas Temperature 1 ? Data Valid but Above Normal Operational Range ? Least Severe Level. High catalyst inlet temperature has been detected.

Cummins ISB CM850 (2003-06) Fault Code: 1716 PID: SPN: 411 FMI: 11 Auxiliary Temperature Sensor Input 1 Circuit – Root Cause Not Known. High temperature detected by the OEM temperature sensor or by the engine coolant temperature sensor.

Cummins ISB CM850 (2003-06) Fault Code: 1713 PID: SPN: 3363 FMI: 0 Catalyst Tank Heater Circuit – Data Valid But Above Normal Operating Range – Moderately Severe Level. The catalyst tank heater is continuously in the on position.

Cummins ISB CM850 (2003-06) Fault Code: 1712 PID: SPN: 3363 FMI: 1 Catalyst Tank Heater Circuit ? Data Valid But Below Normal Operating Range ? Moderately Severe Level. The catalyst solution temperature did not increase when the catalyst tank heater was commanded on.

Cummins ISB CM850 (2003-06) Fault Code: 1711 PID: SPN: 3361 FMI: 9 Dosing Control Unit Data Link ? Abnormal Update Rate. Data Link communications between the ECM and the Dosing Control Unit have been interrupted.

Cummins ISB CM850 (2003-06) Fault Code: 1699 PID: SPN: 1761 FMI: 2 Catalyst Tank Level Sensor – Data Erratic, Intermittent, or Incorrect. Catalyst solution level is not changing with engine operating conditions.

WARNING!