General Motors Drive Cycle

General Motors Drive Cycle For Smog Check

In order to get all your OBD2 monitors for your GM (Chevy, Buick, Cadillac, GMC, Pontiac, Oldsmobile) vehicle ready, please perform the following steps:

  • Start the vehicle from a cold start. The time to do this is if you have not driven the vehicle for a few hours and the engine coolant temperature is less than 50 degrees F.
  • Let the engine run on idle. Turn the A/C and rear defroster on. You are trying to apply electrical load to the system.
  • Accelerate to 55 mph.
  • Hold a steady speed of 55 mph for 3 minutes
  • Let go of the accelerator and coast until the vehicle hits 20mph. Don’t apply brakes to slow down.
  • Accelerate again until 60 mph.
  • Hold steady for 5 minutes at 60mph for 5 minutes.
  • Decellerate (coast to slow down).
  • You may need to repeat steps 3-8 a few times if the battery was disconnected recently.