Originally posted by Ed98.5SVT:
It takes a long time for the cat efficiency tests to run depending on your driving style.



I've had no trouble making them run with the following method:

Drive for at least 4 miles in stop-and-go traffic with about 2-3 stops. (I'm not actually sure this is required to get the cat monitors to run, but this is required to get to the road I used for the below step):

Then drive for at least 6 miles in non-stop traffic at speeds between 45MPH and 65MPH--I used cruise control at about 60MPH, but I have had them run without using cruise control. Apparently, if you exceed 65MPH, the cat tests may not run.