I have a 2002 GS300, I just replace my plugs and wires, cleaned throttle body and maf sensor, the reason why i did that was because it lost power and 3 plugs were bad i think the codes were P301,P303,P305. Now my CIE is coming on and showing a code of P0420 I know it has something to do with the o2 Sensor's, I want to change them out but I think there is a total of 5 and I dont have all the cash to change at one time. So does anyone have or had this problem before and please share info with me. I would like the part numbers of all o2 sensors and a cheap deal on them if there is one out there. Would it be better to by the universal or the exact fit, besides cutting the wire and placing the pins what else is the diffrence. SO CAN ANYONE HELP ME FIGURE OUT WHICH o2 SENSOR TO CHANGE FIRST SO THE LIGHT CSN GO AWAY.
Thanks
John
