A Symptoms

SYMPTOMS

IMPORTANT PRELIMINARY INSPECTIONS BEFORE STARTING
Perform the Diagnostic System Check - Vehicle in Vehicle DTC Information and verify all of the following items:
- The powertrain control module (PCM) and malfunction indicator lamp (MIL) are operating correctly.
- Ensure no DTCs are stored.
- Scan tool data is within normal operating range. Refer to Scan Tool Data List. Scan Tool Data, Normal Values and Definitions
- Verify the customer concern.
- Perform the Visual/Physical Check.

VISUAL/PHYSICAL CHECK
Several of the symptom procedures call for a careful visual and physical inspection. This can lead to correcting a condition without further tests and can save valuable time. This inspection should include the following areas:
- Inspect the PCM grounds for being clean, tight, and in their proper location.
- Inspect vacuum hoses for splits, kinks, and proper connections, as shown on Vehicle Emission Control Information label. Inspect thoroughly for any type of leak or restriction. Refer to Emission Hose Routing Diagram.
- Inspect the air intake ducts for being collapsed, damaged areas, looseness, improper installation, or leaking, especially between the mass air flow (MAF) sensor and the throttle body.
- Inspect for air leaks at throttle body mounting area, MAF sensor and intake manifold sealing surfaces.
- The ignition wires are not cracked, brittle, or carbon tracked.
- Inspect the wiring harness for poor connections, pinches, cuts, or other damage.
- Inspect for loose, damaged, or missing sensors/components.

Use the following tables when diagnosing a symptom complaint:
- 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
- Malfunction Indicator Lamp (MIL) Inoperative
- Malfunction Indicator Lamp (MIL) Always On
- Engine Cranks but Does Not Run