A Symptoms

SYMPTOMS

IMPORTANT PRELIMINARY CHECKS BEFORE STARTING
Perform the Diagnostic System Check - Computers and Control Systems before using the symptom tables. Verify that all of the following conditions are true:
- The engine control module (ECM) and the malfunction indicator lamp (MIL) are operating correctly.
- There are no diagnostic trouble codes (DTCs) stored.
- The scan tool data is within the normal operating range. Refer to Scan Tool Data List. Scan Tool Testing and Procedures

- Verify the customer concern and locate the correct symptom listed below. Inspect items indicated under that symptom.
- Several of the symptom procedures direct the technician to perform a visual/physical inspection. This important step can lead the technician to the cause of the problem without further checks and can save valuable time.
- Verify the correct installation and operation of electronic options, such as lights and cellular phones.

1. Use the following tables when diagnosing a symptom concern:
- Hard Start
- Surges/Chuggles
- Lack of Power, Sluggishness, or Sponginess
- Detonation/Spark Knock
- Hesitation, Sag, Stumble
- Cuts Out, Misses
- Poor Fuel Fill Quality
- Poor Fuel Economy
- Rough, Unstable, or Incorrect Idle and Stalling
- Dieseling, Run-On
- Backfire
2. If the condition cannot be isolated using the appropriate table, refer to Intermittent Conditions for further diagnosis. Intermittent Conditions