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Q: How do you check if readiness codes are set?

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How do you check if readiness codes are set?

If you live in an area that requires annual emissions testing, then you’ll need to know about readiness codes. If these aren’t set, your car can’t be tested and you’ll have to reschedule your emissions test. Here’s how to help ensure they’re set:

  1. Make sure you have three-quarters of a tank of gas (don’t fill it, and don’t let it drop more than this).

  2. Make sure the engine has been off for at least six hours.

  3. The temperature outside should be no lower than 40 degrees F and no higher than 95 degrees F.

  4. Crank the engine but don’t hit the gas. Idle the engine for 20 seconds.

  5. Make sure the car is in park and bring the RPMs up to about 2,000. Keep it there for at least three minutes.

  6. Take your foot off the gas and let the engine drop down to an idle for 20 seconds.

  7. Find a road where you can drive at a steady speed and maintain between 50 and 60 MPH for no less than 20 minutes. Leave cruise control off and keep the transmission in drive. Try to drive for at least a minute and a half without adjusting the gas pedal.

  8. Find an area with traffic and let the car coast for a minimum of 10 seconds. Drive in this area for about 10 minutes.

  9. Park the car and cut off the engine. Let it sit for a half hour.

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