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For 1990-2009 cars only
Makes 🢒 Chevrolet 🢒 2006 🢒 Uplander - 4WD 🢒 General Information 🢒 Vibration Diagnosis and Correction 🢒 Symptoms - Sensors/Systems

Sensor/System

Symptoms

Sensor/System

Find the symptom in the left column and perform the test/inspection procedure in the right column. Be sure to review each cell of the table to identify all tests for a symptom.

    • Hard Start
    • Surges/Chuggles
    • Hesitation, Sag, Stumble
    • Cuts Out, Misses
    • Poor Fuel Economy
    • Rough, Unstable, or Incorrect Idle and Stalling
    • Backfire
    • Inspect the mass air flow (MAF) sensor for proper installation, obstruction, contamination, and damage. Refer to Mass Airflow Sensor Replacement .
    • Inspect the MAF sensor for proper seating of the connector and terminals.
    • Inspect the manifold absolute pressure (MAP) sensor for proper installation, obstruction, and damage. Refer to Manifold Absolute Pressure Sensor Replacement .
    • Ensure the quality of the MAP sensor vacuum source.
    • Hard Start
    • Detonation/Spark Knock
    • Hesitation, Sag, Stumble
    • Poor Fuel Economy
    • Rough, Unstable, or Incorrect Idle and Stalling
    • Inspect for vacuum leaks and other unmetered air. Refer to Emission Hose Routing Diagram .
    • Test the engine coolant temperature (ECT) sensor for being shifted in value. Refer to the Temperature Versus Resistance .
    • Surges/Chuggles
    • Lack of Power, Sluggishness, or Sponginess
    • Detonation/Spark Knock
    • Poor Fuel Economy
    • Backfire

Monitor the Knock Sensor (KS) System for excessive spark retard activity. Refer to the knock sensor description within the Electronic Ignition (EI) System Description .

Hesitation, Sag, Stumble
    • Inspect the accelerator pedal position (APP) sensor and the related wiring. Refer to Throttle Actuator Control (TAC) System Description .
    • Inspect the Throttle Actuator Control (TAC) System for proper operation.
    • Surges/Chuggles
    • Lack of Power, Sluggishness, or Sponginess
    • Hesitation, Sag, Stumble
    • Cuts Out, Misses
    • Poor Fuel Economy
    • Rough, Unstable, or Incorrect Idle and Stalling
    • Backfire

Inspect for contaminated oxygen sensor (O2S).

Poor Fuel Economy

Inspect for proper operation of the speedometer. Refer to Speedometer and/or Odometer Inaccurate or Inoperative .