O2 sensor.

my guess is they tell the computer how to adj air/fuel ratio for best performance.........if the O2 sensor is wacky it may affect performance ie gas consumption or other wise general running......I just changed one in each of my vehicles........and I think they are spendy.....can't 'member the exact cost but not really cheap....hint....wait until the engine/exhaust system has cooled down before trying to remove unit.....hot fingers result ifn you don't wait......

Up until a few years ago I was a mechanic. That means I drive vehicles that could be fixed in an afternoon, but I don't work on my own cars. So I drive cars with check engine lights on, rough idling, poor gas milage, etc.

That being said, A car my wife had had the check engine light on for about the last two years we had the car. The computer showed the code to be an 02 sensor. I don't check gas milage, but it didn't seem any worse than before. It didn't idle rough. It just had that damm check engine light on. I told her to "drive it and let the problem develop" During that time I was secretly hoping the light would burn out. It never did.

That would be my advice to you. then go fishing. By the way, did you get that one handed casting and realing worked out?

I hope this helps. If she has any questions feel free to have her call me. I will help in any way I can.

Wing master

Thanks guys.

I will change the filters, that seems possible, as the CE light does go on and off.....intermittently.

Just got back from 3 days fishing (watching).  Just can't fish, cast on left hand, bad thumb on right.  I couldn't even wind them in after caught.  I did set one hook on a blue.

Figure we can live with the sensor light.  seems to run good.

Present solution is a small piece of black electrician's tape over light.  fixed!  wife can't see the tape.