O2 sensor

[terryc]

I just replaced all 4 O2 Sensors and they all look the same but varying wire lengths. Purchased Denso from Rockauto $297.00 A$ delivered to my door within 6 days. I read on a thread on another Jeep forum that some guys had problems with Bosch, so i opted for the Denso.

[turbomart]

The rear sensors only tell pcm if cats are ok.The front ones are used for fuel ratio trim.

[mlowe76]

turbomart,

so your saying if i'm having worse than normal fuel usage

I'm best to change the front one first? and perhaps not worry bout the rear?

[bikemat]

replace both, if you replace one but not the other you'll no doubt have problems as they degrade over time

[turbomart]

Yeah thats right ,providing its not throwing fault codes for the rear ones.

[mlowe76]

Well its actually a 96 ZG.

It throws up code 21,which isnt very clear as to if its the front or rear one.

I'll just do both next pay day to be safe.

I am getting about 17/100 when I drive hard. Maybe thats actually ok, but for the money I might just change them.

[drover]

I just bought a universal one from REPCO for $130, fitted my old socket to it and everything been working great since, only replaced the front one though, I think the only difference is the cable length. If you don't do fiddly soldering then buy the one with the socket fitted saves a lot of stuffing around but I needed one NOW as my ZG was dead in the water. As far as I know the front one gives the info for fuel mix etc and the rear one doesn't do much at all.