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Home >> Pontiac >> 2003 >> Vibe Base, AWD >> Repair and Diagnosis >> Engine Performance >> System >> Engine Control System - Self-Diagnostics >> Self-Diagnostic System >> Diagnostic System Check - Engine Controls >> Diagnostic Procedures
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Diagnostic Procedures

  1. Connect scan tool. Does scan tool power-up? If yes, go to next step. If no, perform SCAN TOOL DOES NOT POWER UP in appropriate BODY CONTROL MODULES article in ACCESSORIES & EQUIPMENT.
  2. Turn ignition switch to RUN position, engine OFF. Attempt to establish communication with Powertrain Control Module (PCM). Does the scan tool communicate with PCM? If yes, go to next step. If no, go to SCAN TOOL DOES NOT COMMUNICATE WITH PCM in appropriate BODY CONTROL MODULES article in ACCESSORIES & EQUIPMENT.
  3. Attempt to start engine. Does engine start and idle? If yes, go to next step. If no, go to ENGINE CRANKS BUT DOES NOT RUN under NO-START DIAGNOSIS in BASIC DIAGNOSTIC PROCEDURES - 1.8L VIBE article.
  4. Select the DTC display function for the PCM. Does scan tool display any powertrain DTCs? If yes, go to next step. If no, go to step  7.
  5. Using scan tool, save or capture the powertrain DTC information and store information. When complete, go to next step.
  6. Does scan tool display DTC P1600? If yes, go to P0601-P0607, P1600, P1621, P1627, P1680, P1681, P1683 Or P2610: ECU MALFUNCTION  under DIAGNOSTIC TESTS. If no, go to DIAGNOSTIC TROUBLE CODE DEFINITIONS .
  7. Is customer's concern related to the automatic transmission? If yes, diagnose transmission problems. See appropriate DIAGNOSIS article in AUTOMATIC TRANSMISSIONS. If no, go to next step.
  8. Is customer's concern with Inspection/Maintenance (I/M) testing? If yes, see INSPECTION/MAINTENANCE SYSTEM CHECK  under DRIVE CYCLES. If no, go to next step.
  9. Check for the following symptoms:
    • Hard start.
    • Surges/chuggles.
    • Lack of power, Sluggishness/sponginess.
    • Detonation/spark knock.
    • Hesitation, sag, stumble.
    • Cuts out, misses.
    • Poor fuel economy.
    • Poor fuel fill quality.
    • Rough idle, unstable idle, incorrect idle and stalling.
    • Dieseling, run-on.
    • Backfire.
    • MIL inoperative.
    • MIL always on.
    Did you find and correct the condition? If yes, system is okay. If no, problem is intermittent. See INTERMITTENTS in TROUBLE SHOOTING - NO CODES - 1.8L VIBE article.
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