I'm going to replace my o2 sensors because i've been getting higher fuel usage lately plus the fact i've done 140,000klm with the factory ones. My only problem is which ones to go for. I've had a look around the web and come the conclusion that 1997-1999 TJ's have 2 o2 sensors which are:
Pre Cat NTK #231151
Post Cat NTK #23099
2000+ TJ's supposedly have 4x o2 sensors. 2000 TJ's sensor list:
Rear Pre-Cat upstream NTK #23506
Rear Post-Cat downstream NTK #23099
Front Pre-Cat upstream NTK # 23099
Front Post-Cat downstream # 23110
2001-2003 are listed as:
Front Pre-cat NTK #23139
Front Post-cat NTK #23142
Rear Pre-cat NTK #23138
Rear Post-cat NTK #23141
And then there's another 4 different part numbers for 2004+ TJ's.
My problem is than according to my VIN# mine's a 2002 (which makes sense seeing as i bought it new from the dealer in 2002) however i can only find 2x o2 sensors. I don't seem to have any little cat converters up near the headers that i know later models supposedly had. I can only find 2x sensors in the exhaust system located before and after the cat converter which is located down above the t-case bashplate.
Does this mean that i should go with the 97-99 model o2 sensors as those years appear to be the only ones in the US that only had 2x o2 sensors?
Has anyone else had this issue? Can anyone else with a 2002 TJ confirm that they've only got 2x o2 sensors or is my TJ a weird one? Mine was bought new in australia and is a right hand drive TJ. Perhaps because it's an export there is a difference?