My question is do you have to return the computer to stock set up before having a emission test done on a vehicle? Before I buy one I want to know if I have to do this or not....Thanks

 

I'm sure if I'm wrong I'll get corrected, but to the best of my knowledge no you don't. In fact it would be bad to do so if in your area they use the truck's computer to do the emissions test. If you reset your program you'll also erase the stored info causing an invalid test.

 

You should have no problems with it. Its 50 state legal and CARB certified.