Q: How do you make sure readiness codes are set in the computer for emissions testing?

If you live in an area where emissions testing is mandatory, you’re no doubt familiar with the hassle of not being able to test your car if the readiness codes aren’t set. Thankfully, there’s a way you can help make sure that the re-test is successful. Follow these steps:

1. Fill your gas tank only about three-quarters of the way.

2. Park the car and leave the engine off for a minimum of 6 hours.

3. Make sure the outside air temperature is at least 40 degrees F and no higher than 95 degrees F.

4. Start the engine (don’t touch the gas).

5. Let it idle for 20 seconds (keep that foot off the gas).

6. Lightly touch the gas pedal and increase the engine RPMs to 2,000. Hold that for about 3 minutes, or until the temperature gauge rises about a fourth of the way up.

7. Let off on the gas and let the car idle for another 20 seconds (again, no using the accelerator).

8. Find a road with little traffic and drive at 60 MPH. Maintain that speed for about 20 minutes. Don’t engage the cruise control system, either. When possible, keep the accelerator pedal in the same position for about a minute and a half.

9. Find an area where traffic is “normal” and drive for about 10 minutes. Try to let the car coast for 5 seconds or so without touching the brake or the gas.

10. Park the car for at least a half hour before having your test performed.