EVA and couple other codes what does it mean

[comet240]

hi i got 2 cars i currently working on both 2.2

the one i replaced the O2 sensor as my Innova scan tool was flashing 02s and EVA after driving for a while the O2S light stopped blinking but the EVA still blinking what would most commonly to be replaced its on a 2.2 97 sunfire (yes i know wrong form but no one replies in Sunfire and same engine as my cav)

and on the other sunfire its a 98 it has 6 lights flashing EVA, 02S, HTR,CAT, HCA,EGR

i replaced the 02 sensor like on other car but i couldnt drive on road no plates so i jacked it up and drove it at 60km for like 20 km 2 sets of 10km but its still flashing

what does each one do like HTR is some heater for the O2 sensor but i dont know where that heater is ?

any help be great