Originally Posted by
hg2
Yes but this time start with just the O2 efie and start with 200mv(.2v)and slowly bring it up a little a at time driving a day or so between tweaks.If you see the mpg gains you want without setting any codes I'd leave it there.The map en. is more adpt to set codes than the O2 efie,but every vehicle different so if you're not satisfied with your results using O2 efie then install the map en. and lower the voltage on the O2 efie and start over with the tuning process with small tweaks on both with a day or so driving between them.