I did have a check engine light, but I deleted my EGR and rear O2 sensors. My area doesn't check for emissions. You will need to use the donor's evap system, which mainly consists of a sensor in the fuel tank. This should be easily adaptable. If you plan to get a tuner any time in the near future, you can get a custom tune to delete the emissions from the ECU, which will not be detectable at the testing station, which is something I have looked into when I did my Trac V8 swap...