Important Preliminary Inspections Before Beginning

Before using this section, perform the Diagnostic System Check - Vehicle and verify all of the following conditions:

• The powertrain control module (PCM) and the malfunction indicator lamp (MIL) are operating correctly. Refer to Malfunction Indicator Lamp (MIL) Inoperative .
• Diagnostic trouble codes (DTCs) are not stored.
• The scan tool data is within the normal operating range. Refer to Scan Tool Data List .
• Verify the customer concern and locate the correct symptom table. Inspect the items indicated in that symptom table.
• Several of the symptom procedures ask for a careful visual/physical inspection. This step is extremely important, and can lead to correcting a condition without further inspections and can save valuable time.
• If the intermittent condition exists as a start and then stall, inspect for any DTCs related to the theft deterrent system. Refer to Diagnostic System Check - Vehicle .
• Verify the proper installation of any of the following aftermarket accessories:
  • Lights
  • Cellular phone
  • Remote starter system
  • Aftermarket installed alarm
• Use the following tables when diagnosing a symptom concern:
  • Poor Fuel Fill Quality
  • Hard Start 
  • Surges/Chuggles 
  • Lack of Power, Sluggishness, or Sponginess 
  • Detonation/Spark Knock 
  • Hesitation, Sag, Stumble 
  • Cuts Out, Misses 
  • Poor Fuel Economy 
  • Rough, Unstable, or Incorrect Idle and Stalling 
  • Dieseling, Run-On 
  • Backfire 
• If the condition cannot be isolated using the appropriate table, refer to Intermittent Conditions  for further diagnosis.