What does the oxygen sensor actually do? My white wire has been worn through. I'll be replacing it tomorrow, but what does it actually do? Thanks

Oxygen sensor lights up the LED's in the ECU, in a particular pattern. This determines wheather or not your mixture adjustment is set correctly.

I think youv'e got yourself a bit confused Sckottey, The computer only does that when it is in its tuning mode thingy, The sensor is used by the computer to work out air/fuel ratios, in other words, if the sensor sees that there is not enuf oxogen in the exhaust gas, the computer adjusts the amount of fuel it is firing. There is more to it than just this, but thats the basics of what it does.

bluvlt is right, the oxygen sensor does alot more than U think. It should be replaced every 80,000 kms or so. They get all clocgged up with **** and carbon crap, and then they dont work. They are oly about 70 dollars (In sydney for a NGK One). Ive replacd mine, and left the computer without power over night so it can resent and learn the new Lamba paterns (Oxy Sensor). All is good now :!: Some original photos have not been recovered yet.

Quote: Originally Posted by vl_grunt bluvlt is right, the oxygen sensor does alot more than U think. It should be replaced every 80,000 kms or so. They get all clocgged up with **** and carbon crap, and then they dont work. They are oly about 70 dollars (In sydney for a NGK One). Ive replacd mine, and left the computer without power over night so it can resent and learn the new Lamba paterns (Oxy Sensor). All is good now :!: Thats a good price mate - where from??? Last time i had to get one it was like $250 8O Some original photos have not been recovered yet.

yeah where did u get it for that price?? u sure ur not thinking of the single wire sensor?? i priced a newie last week, they wanted $280!!

That price I got from a Local Autobarn Place in Sydney. Its a NGK one, so its not a bodgy one. Holden wanted some dumb ass price like that 200 bux or summfin, so I said GET F... hehe u can work it out. Went out shopping and found the same thing for heaps cheaper. Ring around, ask any mates of yours that are mechanics, they are bound to know sum1 who can get it a bit cheaper than retail (say for about 70-80 bux) Its a 3 wire, identicle to the old one I took out. I'll have a look on the box see if theres a sydney contact or email, maybey you can buy direct from the supplier(s)� I got mine a little cheaper (being 70 rather than 90) because I know the due who runs the Auto place, but still, 90 retail is heaps better than holden or nissans stupid price. Cheers :P

you need a oxygen sensor to run a loopback mode on your ecu. if u dont have one then it is illegal haha "yes officer I have one" Some original photos have not been recovered yet.

a couple of weeks ago there was a mod posted for n/a's where the afm was adjusted so the resistance between terminals 1 and 6 was 382 ohms. i presume this made the air fuel mixture richer and supposedly gave more power. my question is, if the oxygen sensor senses too much oxygen in the exhaust and adjusts air/fuel via the computer, then does it work the other way and sense if there is too much fuel in the exhaust due to a rich mixture and readjust the mixture to run leaner, hence making this mod inoperable?

Adjusting the AFM really does not do alot for when you driving normally. When your cruising along, the cars ECU runs in a closed loop state, so the AFM adjustment doesn�t mean much to the ECU, it still measures air intake but the oxygen sensor is constantly trying to keep the car running at 14.7 stiomatic which is the normal level. I wouldn�t recommend changing the AFM setting, as its factory setting of 3.58 volts is sufficient for most purposes.

vl grunt, did u replace it due to poor fuel economy? did it make a difference?

Quote: Originally Posted by SIK VL vl grunt, did u replace it due to poor fuel economy? did it make a difference? Sik VL, yes i originally replaced due to poor fuel economy. The main reson being is because after about 80,000km or so it is reccomended that you change the Oxygen sensor, because the special chemicals on the ceramic probe inside, generally wear off and loose their 'sensitivity'. Alos the other thing that made me REALLY wanna change it was after i got my new motor. New motor, new Oxy sensor, you know start from scratch, the old motor I had burnt that much oil, the oxygen sensor was fouled up and **** itself basiclly.

Yeah ive just had my engine rebuilt. But 280km to a tank isnt good enough, ive worked out its either the o2, temp sensor of AFM maybe a combination. Is there a particular resistance on the components i should be looking for? the temp sensor, is that a variable resistor or on/off? maybe ill just get a sparky to look at it.

i was quoted $130 fitted for a new oxy sensor from an exhaust place (good old dave @ ozfit ) he did my exhaust and i asked him if the oxy sensor could be causing the ****ty fuel economy. he had a look at it and said yeah its rooted (actually he said "aw nah nah nah yeah its ****ed *chews chewy*"). sold it before i got a new one though. Some original photos have not been recovered yet.

Quote: Originally Posted by dr00 i was quoted $130 fitted for a new oxy sensor from an exhaust place (good old dave @ ozfit ) he did my exhaust and i asked him if the oxy sensor could be causing the ****ty fuel economy. he had a look at it and said yeah its rooted (actually he said "aw nah nah nah yeah its ****ed *chews chewy*"). sold it before i got a new one though. hey dr00, you shouldnt need to get it fitted man, its piss easy to put in, like un do it and turf the old one, plug in the new one. If its fuc#ed, i'd replace it, it plays a big part in engine managment. Some original photos have not been recovered yet.

Quote: Originally Posted by SIK VL Yeah ive just had my engine rebuilt. But 280km to a tank isnt good enough, ive worked out its either the o2, temp sensor of AFM maybe a combination. Is there a particular resistance on the components i should be looking for? the temp sensor, is that a variable resistor or on/off? maybe ill just get a sparky to look at it. Sik VL, the temp sensor is a big variable resitor if u wanna look at it like that. It changes its value according to how hot the coolant is. They dont usually die, although i guess its not impossible. The gregorys manual tells you how to test the temp sensor and to test ya mixture. Id try those things first. The AFM, as I have said so many times in similar posts, should not need to be touched if it hasnt been screwdriveres by a screw driver jockey Some original photos have not been recovered yet.

Do u need to rewire the new o2 sensor to the old ones wires ?

No theres a plug. Plug in/ plug out. VLGRUNT, theres actually a cable tie on my temp sensor, so ill get it looked at. Yeah i cant be stuffed heating up a bowl of water with a bunsen burner or what eva. so i should be looking to pay around 90-150ish for an o2? temp sensor should be about the same i guess. ill be looking into it.

Quote: hey dr00, you shouldnt need to get it fitted man, its piss easy to put in, like un do it and turf the old one, plug in the new one. If its fuc#ed, i'd replace it, it plays a big part in engine managment. i didnt say i was gonna get him to do it. the guy just did my exhaust and i asked him. he said he'd do it for that much. i just wanted to know if it was rooted.

Ive heard that there are ways to clean the sensor for better clarity, cant remember exactlty but think it involved dipping it in some kind of cleaner, or may have been petrol :? anyone know?