Diagnostic Aids

The injector balance test on the scan tool should be used to confirm fault cylinder problems. The scan tool will cut out the specific cylinder requested. The PCM will increase or decrease fuel to other cylinders to compensate for a rough idle if a cylinder balance fault is detected over a long period of time. This can cause multiple cylinder balance DTCs to set. The scan tool snap shot mode can be used to properly identify the suspected cylinder. The most likely cause of cylinder balance DTCs are malfunctioning nozzles.

If multiple cylinder balance DTCs are set and no problem is found, check for the following conditions:

• Pinched or restricted fuel feed lines between fuel tank and fuel injection pump
• Restricted fuel filter