I/M Readiness Drive Cycle Test Procedure

I/M Readiness Drive Cycle Test Procedure

  • Vehicle should be started with the engine cold.
  • Let vehicle idle until the engine is at normal operating temperature (the engine coolant temperature sensor should read 180° F of higher). Generally 5 to 10 minutes is sufficient depending on outside ambient temperature.
  • Put vehicle in gear (with brake applied) and idle for no less than 45 seconds.
  • Accelerate to 45 MPH with no more than 1/4 throttle and maintain speed for a full 10 seconds.
  • Decelerate to 35-38 MPH and maintain a steady throttle and speed for 1 minute.
  • Decelerate to 25 MPH and then operate between 25 MPH and 40 MPH for 4 minutes. DO NOT operate at more than 3/4 throttle for this test segment.
  • Decelerate and idle engine for 10 seconds.
  • Accelerate gently to 55 MPH using NO MORE than 1/2 throttle, maintain speed for a full 10 seconds.
  • Continue driving at 40 MPH - 55 MPH, Use a steady throttle pressure and maintain speed for a full 2 minutes.
  • Return to your shop and shut the vehicle off.
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