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Home >> Jeep >> 2002 >> Wrangler X, Automatic >> Repair and Diagnosis >> Engine Performance >> System >> Engine Controls - Basic Diagnostic Procedures >> DRIVEABILITY Problems >> Start & Stall Condition
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Start & Stall Condition

NOTE: For circuit identification and wiring diagram, see WIRING DIAGRAMS article. After each repair procedure has been completed, reconnect all components. Perform POWERTRAIN VERIFICATION TEST VER-1  under VERIFICATION TESTS to ensure system is functioning properly.
  1. Turn the ignition on. With the DRBIII(R), read DTCs. Are any DTCs present? If yes, See DIAGNOSTIC TROUBLE CODE DEFINITIONS in appropriate SELF-DIAGNOSTICS article. If no, go to next step.
  2. With the DRBIII(R), read the SKIM codes. Are there any SKIM DTCs? If yes, a fault exists in anti-theft system. Perform appropriate test. See appropriate ANTI-THEFT SYSTEMS article. If no, go to next step. If unable to communicate with the SKIM, diagnose communication fault. See COMMUNICATIONS under SYSTEM TESTS in appropriate BODY CONTROL MODULES article in ACCESSORIES & EQUIPMENT.
  3. With the DRBIII(R), read TP Sensor volts. While monitoring the DRBIII(R), slowly open and close the Throttle. Is the voltage change smooth? If yes, go to next step. If no, replace the Throttle Position Sensor.
  4. With the DRBIII(R), read Throttle Position voltage. Throttle must be against stop. Is the voltage 0.92 volt or less with the Throttle closed? If yes, go to next step. If no, check for a binding throttle condition. If okay, replace the Throttle Position Sensor.
  5. For this test to be valid, the thermostat must be operating correctly. This test works best if performed on a cold engine (cold soaked). If the vehicle was allowed to sit over night with no engine start, coolant temperature should be near ambient temperatures. Turn the ignition on. With the DRBIII(R), read the Engine Coolant Temperature value. If engine coolant temperature is above 180°F (82°C), allow the engine to cool until 150°F (65°C) is reached. Start the engine. During engine warm-up, monitor the Engine Coolant Temperature value. The temperature value change should be a smooth transition from start up to normal operating temp 180°F (82°C). The value should reach at least 180°F (82°C). Did the Engine Temperature value increase smoothly and did it reach at least 180°F (82°C)? If yes, go to next step. If no, replace the Engine Coolant Temperature Sensor.
  6. Check the following additional items as possible causes for start and stall condition:
    • Check for any technical service bulletins that may apply.
    • Engine exhaust system must be free of restrictions.
    • Engine compression must be within specification.
    • Engine valve timing must be within specification.
    • Engine must not have any vacuum leaks.
    • Throttle body must be free of carbon build-up and dirt.

    Do any of the above conditions exist? If yes, repair as necessary. If no, go to next step.

  7. Verify that the Fuel tank is not empty before continuing. Check fuel delivery. See FUEL SYSTEMS in SYSTEM & COMPONENT TESTING article. Was the No-Start condition solved after following the above diagnostic test? If yes, test is complete. If no, check for contamination/water in the fuel. Ensure the fuel being used in vehicle meets manufactures Fuel Requirement of a high quality unleaded gasoline having an octane rating of 87.
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