A Symptoms

IMPORTANT PRELIMINARY INSPECTIONS BEFORE STARTING
Before using this section, perform Diagnostic System Check - Computers and Controls Systems to verify the following items:
- The powertrain control module (PCM) and malfunction indicator lamp (MIL) are operating correctly.
- There are no DTCs stored.
- Ensure that the engine coolant temperature (ECT) is not above 130°C (266°F). This will cause the PCM to operate in the Engine Metal Overtemp Mode. While in this state, the PCM will turn OFF four cylinders at a time to prevent the engine coolant temperature from reaching damaging levels. Engine Metal Overtemp can be perceived as a lack of power, engine miss, or rough idle.

If the engine is operating in the Engine Metal Overtemp mode, refer to DTC P1258.

- Scan tool data is within the normal operating range. Refer to Scan Tool Data List. Scan Tool Data, Normal Values and Definitions

- Verify the customers complaint to reference the correct symptom table.

VISUAL/PHYSICAL INSPECTION
Several of the symptom procedures call for a careful Visual/physical inspection. This inspection can lead to correcting a problem without further inspections and can save valuable time. This inspection includes the following items:
- PCM grounds for being clean, tight, and in the proper location- Refer to Master Electrical Component List and Power and Grounding Component Views in Diagnostic Aids.
- Vacuum hoses for splits, kinks, proper routing, and connections- Refer to the Vehicle Emission Control Information label. Check thoroughly for any type of leak or restriction. Refer to Emission Hose Routing Diagram.
- Intake air system for the following conditions:
- A dirty or damaged air cleaner element or housing
- Any damaged or collapsed intake air ducts
- Any poor intake air system connections
- Air leaks at the throttle body and/or intake manifold.
- Throttle body contaminants or deposits.
- Accelerator cable binding or damage.
- Ignition system wiring for incorrect routing and/or poor connections.
- System wiring for routing near high frequency devices (electromagnetic interference (EMI) condition).

- Cooling System system leaks. Refer to Loss of Coolant in Cooling System.

The following Symptom tables are located in this section:
- Hard Start
- Surges/Chuggles
- Lack of Power, Sluggishness, or Sponginess
- Detonation/Spark Knock
- Hesitation, Sag, Stumble
- Cuts Out, Misses
- Poor Fuel Economy
- Poor Fuel Fill Quality
- Rough, Unstable, or Incorrect Idle and Stalling
- Dieseling, Run-On
- Backfire
- Restricted Exhaust in Exhaust System