Circuit/System Testing

Operate the engine within the conditions listed in the Freeze Frame Failure Records.
A current misfire should not be indicated.
- If a single cylinder Current Misfire is indicated, inspect the following components of the affected cylinder for proper operation:

If more than one cylinder is randomly misfiring, inspect the following components condition and operation:

The vacuum hoses and seals-Refer to Evaporative Emissions (EVAP) Hose Routing Diagram .
The throttle body and intake manifold
The crankcase ventilation system-Refer to Crankcase Ventilation System Inspection/Diagnosis .
The ECM grounds
The exhaust system-Refer to Restricted Exhaust .
The fuel-Refer to Alcohol/Contaminants-in-Fuel Diagnosis .
The spark plugs-Refer to Spark Plug Inspection .