I noticed the check engine light was on in my 2000 Ranger 3.0, I had a mechanic buddy hook up his machine to it and the code for a slow responding oxygen sensor came up. It seems like I'm not getting very good gas millage right now and the idle is a little rough. Could the oxygen sensor be the cause of this? If it's too difficult to replace I'll have my buddy do it, but if it's not to bad I'd like to give it a shot, but I don't work on cars very often any more. Any opinions?!?!?