i have a 88 4runner 4 cyl efi.i put a bosh 02 sensor in it and the engine light came on drove it a hundred miles.then i put an oem toyota 02 sensor on.light still comes on and it smells like gas rich exaust.i didnt reset the computer.could i have burned it up??i dont want to buy a new one as ive already spent 300.00 on 2 o2 sensors. its spitting codes 25 and 26.thnx for any help..