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Symptom Troubleshooting Index

These symptoms DO NOT trigger diagnostic trouble codes (DTCs) or cause the malfunction indicator lamp (MIL) to come on. If the MIL is reported on, check for DTCs. If the vehicle has one of these symptoms, do the diagnostic procedure for it, in the sequence listed, until you find the cause.

SYMPTOM TROUBLESHOOTING INDEX

Symptom Diagnostic procedure Also check for
Engine will not start (MIL works OK, no DTCs set)
  1. Test the battery (see SELF-DIAGNOSTIC FUNCTION ).
  2. Test the starter (see CRUISE CONTROL ACTUATOR CABLE REPLACEMENT ).
  3. Test the fuel pump (see FUEL PUMP TEST ).
  4. Troubleshoot the PGM-FI main relay circuit (see PGM-FI MAIN RELAY CIRCUIT TROUBLESHOOTING ).
  • Low compression
  • No ignition spark
  • Intake air leaks
  • Locked up engine
  • Broken cam chain
  • Contaminated fuel
Engine will not start (MIL comes on and stays on, or never comes on at all, no DTCs set) Troubleshoot the MIL circuit (see MIL CIRCUIT TROUBLESHOOTING ).  
Engine will not start (immobilizer indicator stays on or flashes) Troubleshoot the immobilizer system (see HID BULB REMOVAL ).  
Engine is hard to start (MIL works OK, no DTCs set)
  1. Test the battery (see SELF-DIAGNOSTIC FUNCTION ).
  2. Test the fuel pressure (see FUEL PRESSURE RELIEVING ).
  • Low compression
  • Intake air leaks
  • Contaminated fuel
Cold fast idle too low (MIL works OK, no DTCs set)
  1. Do the ECM idle learn procedure (see IDLE SPEED INSPECTION ).
  2. Inspect the idle speed (see IDLE SPEED INSPECTION ).
  
Cold fast idle too high (MIL works OK, no DTCs set)
  1. Do the ECM idle learn procedure (see IDLE SPEED INSPECTION ).
  2. Inspect the idle speed (see IDLE SPEED INSPECTION ).
  3. Inspect/adjust the throttle cable (see THROTTLE CABLE ADJUSTMENT ).
  4. Inspect and test the throttle body (see THROTTLE BODY TEST ).
  
Idle speed fluctuates (MIL works OK, no DTCs set)
  1. Do the ECM idle learn procedure (see IDLE SPEED INSPECTION ).
  2. Inspect the idle speed (see IDLE SPEED INSPECTION ).
  3. Inspect/adjust the throttle cable (see THROTTLE CABLE ADJUSTMENT ).
  4. Inspect and test the throttle body (see THROTTLE BODY TEST ).
 Intake air leaks
After warming up, idle speed is below specification without load (MIL works OK, no DTCs set)
  1. Do the ECM idle learn procedure (see IDLE SPEED INSPECTION ).
  2. Troubleshoot the alternator FR signal circuit (see ALTERNATOR FR SIGNAL CIRCUIT TROUBLESHOOTING ).
  3. Troubleshoot the A/C signal circuit (see A/C SIGNAL CIRCUIT TROUBLESHOOTING ).
  4. Troubleshoot the electrical power steering (EPS) signal circuit (see ELECTRICAL POWER STEERING (EPS) SIGNAL CIRCUIT TROUBLESHOOTING ).
  5. Test the throttle body (see THROTTLE BODY TEST ).
 Faulty throttle cable
After warming up, idle speed is above specification without load (MIL works OK, no DTCs set)
  1. Do the ECM idle learn procedure (see IDLE SPEED INSPECTION ).
  2. Troubleshoot the alternator FR signal circuit (see ALTERNATOR FR SIGNAL CIRCUIT TROUBLESHOOTING ).
  3. Inspect the TP Sensor (see THROTTLE POSITION SENSOR SIGNAL INSPECTION ).
  4. Troubleshoot the A/C signal circuit (see A/C SIGNAL CIRCUIT TROUBLESHOOTING ).
  5. Troubleshoot the electrical power steering (EPS) signal circuit (see ELECTRICAL POWER STEERING (EPS) SIGNAL CIRCUIT TROUBLESHOOTING ).
  
Low power (MIL works OK, no DTCs set)
  1. Test the fuel pressure (see FUEL PRESSURE RELIEVING ).
  2. Inspect and test the throttle body (see THROTTLE BODY TEST ).
  3. Inspect/adjust the throttle cable (see THROTTLE CABLE ADJUSTMENT ).
  • Low compression
  • Incorrect camshaft timing
  • Incorrect engine oil level
Engine stalls (MIL works OK, no DTCs set)
  1. Do the idle learn procedure (see IDLE SPEED INSPECTION ).
  2. Test the fuel pressure (see FUEL PRESSURE RELIEVING ).
  3. Inspect the idle speed (see IDLE SPEED INSPECTION ).
  4. Troubleshoot the brake pedal position switch signal circuit (see BRAKE PEDAL POSITION SWITCH SIGNAL CIRCUIT TROUBLESHOOTING ).
  • Intake air leaks
  • Faulty harness and sensor connections
Difficult to refuel (MIL works OK, no DTCs set)
  1. Test the fuel tank vapor control valve (see FUEL TANK VAPOR CONTROL VALVE TEST ).
  2. Inspect the fuel tank signal tube between the fuel pipe and the fuel tank vapor control valve.
  3. Inspect the fuel tank vent tube between the EVAP canister and the fuel tank vapor control valve.
  4. Check the EVAP canister.
 Malfunctioning gas station filling nozzle.
Fuel overflows during refueling (No DTCs set) Replace the fuel tank vapor control valve (see FUEL TANK VAPOR CONTROL VALVE REPLACEMENT ). Malfunctioning gas station filling nozzle.
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