Like a dummy I mistakenly erased the computer codes and I need to get the truck smog tested. It won't pass until all the computer tests have been completed. I have driven it for over 200 miles and the computer still says 3 of it's tests are not completed yet! Anybody know how many miles I need to drive until the computer is ready for a smog test?

Thanks in advance,
Andy

 

It's a little more complicated than that. The computer only runs any given test under certain operating conditions. If you know what all the operating conditions are and how long they have to last you can run a drive cycle (ie allow the computer to run all the tests) in a half hour. The parameters will be run at idle for x ammount of time, drive between 30-50mph for x ammount of time... stuff like that.

My advice would be, if you ran most of that 200 miles on the highway then spend some time on back roads or around town with red lights and stop signs if you have that option. Maybe let the truck idle for 10 min or so...

Maybe one of the gm techs on here could offer more input.

 

You can get most of the monitors to run by performing a drive cycle as described at this link General Motors Driving Cycle but it's not a full guarantee they all will finish.

As mentioned by bfg112, each monitor requires specific operating conditions to be met before they will run. It would be a long list to describe each one of them here. If you are curious, try searching on the internet. I'm sure you will find something about each of them. The hardest monitors to get to run their tests are the catalyst and EVAP systems. These two can take awhile.

One condition for the EVAP monitor for instance is the fuel tank level. This monitor won't run if your tank is full or near empty. Your fuel level needs to be between 15% and 85% for this one to run. Even then, if other conditions are not met, it won't run anyway.

Good luck