GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 GMC_Truck 🢒 2002 🢒 Safari - 2WD 🢒 Engine 🢒 Engine Controls - 4.3L 🢒 Symptoms - Engine Controls

Important Preliminary Inspections

Inspections

Action

Before Using This Section

Before using this section, you should have performed the Diagnostic System Check - Engine Controls . Several of the following symptom procedures call for a careful visual and physical inspection. The visual and physical inspections are very important. These inspections can lead to correcting a problem, which may save valuable time.

  1. Verify the customer complaint.
  2. Locate the correct symptom table.
  3. Inspect the items indicated under that symptom.

Visual and Physical
    • Inspect the powertrain control module (PCM) grounds for being clean, tight, and in their proper location. Refer to Power and Grounding Component Views in Wiring Systems.
    • Inspect the vacuum hoses for splits, kinks, and improper connections, as shown on the Vehicle Emission Control Information label.
    • Inspect thoroughly for any type of leak or restriction in the exhaust. Refer to Exhaust Leakage or Restricted Exhaust in Engine Exhaust.
    • Inspect for vacuum leaks at all the mounting areas of the intake manifold sealing surfaces.
    • Inspect the spark plug wires. Refer to Spark Plug Wire Inspection .
    • The following symptom tables contain groups of possible causes for each symptom. In order to determine if a specific vehicle is using a particular system or component, refer to Powertrain Control Module Connector End Views for an application.

Symptom

Use the following tables when diagnosing a symptom complaint.

    •  Hard Start
    •  Surges/Chuggles
    •  Detonation/Spark Knock
    •  Cuts Out, Misses
    •  Poor Fuel Economy
    •  Dieseling, Run-On
    •  Backfire