my 97 gle check light came on....and i did that little flat head and ecu technique....and 03 04 came up first.....and then 07 07 came up next.....

i kno 03 04 is the KS.
but is 07 07????????????????????
some one please help...lol

 

Yes, 0707 is the rear O2 sensor in the cataylic convertor. Sometimes it will go off randomly without anything wrong with it. Reset the ECU and wait and see if it will come back. If it does, then replace it. It's real easy to replace. Just need an O2 socket tool and access the plug underneath the driver's seat. Your gas mileage will be better once you replace it.

 

From what all the other orgers have said in the past, it has no effect on mileage.

 

Yeah, I guess it all depends on different experiences. When i had my '95, I had a bad rear O2 sensor and ran the car for months knowing it was bad. At the time, my money was tight, so it took me a while to repair it. Anyway, once I replaced it, I did see an increase in gas mileage somewhat. The rear O2 sensor does play a small part in the air/fuel ratio.

 

rear o2 only monitors emissions, has no effect at all on air/fuel ratio. The only benefit from gas mileage MIGHT come from the ECU not running in error/failsafe mode.

I've beeng missing with a simulator for some time, but the check engine light keeps coming back on, so I'm going to buy a new one.