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Home >> Saturn >> 2003 >> Ion 1 Standard >> Repair and Diagnosis >> Engine Performance >> System >> Engine Controls - Trouble Shooting >> Symptoms >> Restricted Exhaust >> Diagnostic Procedure
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Diagnostic Procedure

  1. Verify the customers complaint. Test the vehicle under the same conditions that the customer reported to verify the system is operating as designed. Go to next step.
  2. Did you review the exhaust symptoms diagnostic information and perform the necessary inspections? If yes, go to next step. If no, go to VISUAL/PHYSICAL INSPECTION  .
  3. Remove the Heated Oxygen Sensor (HO2S) that is in front of and closest to the catalytic converter. Install the Gauge Bar Set (SA9127E) or Exhaust Back Pressure Gauge (J 35314-A) in place of the HO2S sensor. Start the engine. Increase and monitor the engine speed at 2000 RPM. Observe the exhaust system back pressure reading on the gauge. Does the reading exceed 2 psi (14 kPa)? If yes, go to next step. If no, go to step  7 .
  4. Turn the engine off and place the ignition switch in the LOCK position. Remove the gauge bar set or backpressure gauge. Re-install the HO2S sensor. Remove the post-catalytst HO2S sensor. Install the Gauge Bar Set or Exhaust Back Pressure Gauge in place of the post HO2S sensor. Start the engine. Increase and monitor the engine speed at 2000 RPM. Observe the exhaust system back pressure reading on the gauge. Does the reading exceed 2 psi (14 kPa)? If yes, go to next step. If no, go to step  6 .
  5. Check the exhaust system for the following conditions:
    • Damage in the exhaust pipe.
    • Debris in the exhaust pipe.
    • Muffler or resonator internal failure.
    • Two-layer exhaust pipe separation.

    Repair as necessary. After repair, go to step  7 .

  6. Replace the catalytic converter. After repair, go to next step.
  7. Remove the gauge bar set or back pressure gauge. Re-install the HO2S sensor. Clear any codes using a scan tool. Road test the vehicle to verify the repair. Did you correct the condition? If yes, system is okay at this time. If no, go to step  2 .
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