hi guys,

few months ago i bought an oxygen sensor but i ordered the wrong part,,
then few weeks ago i ordered the right one (i think) but rockauto sent me the wrong part :p

oh well.. they refunded for it and all that, its all good, but now i have two bosch oxygen sensors that look identical apart from the wiring of them.

car is TJ executive 2000,
the sensors i have now are
http://www.rockauto.com/catalog/moreinfo.php?pk=279633&jnid=2&jpid=0
this one has good wiring length and cables are coded same as what i have in there, should be black grey and white white
and
http://www.rockauto.com/catalog/moreinfo.php?pk=279352&jnid=4&jpid=0

the correct part supposed to be this one (i think) as it has the same middle seal cap and same type of connector
http://www.rockauto.com/catalog/moreinfo.php?pk=279638&cc=1364059&jnid=432&jpid=15

now when i look the third picture in that link, i can see that wiring is
white white grey black when the clip lock is on top

wondering if i use the sensor i have (first one with long cable) cut the wires, and join in the same color sequence, would it work ?
would i blow anything up in case wiring is wrong?
or is there a safe way of measuring resistances or anything else with a multimeter to make sure its right?

Today I had the same problem. I bought 2 sensors 'similar' to the one in your first link thinking they would fit my Pajero NH and Magna TF. (About $45 each).

The Pajero one was fine but the plug for the TF was wrong.

The Magna original was an NTK OZA 116 M8. The new sensor was an NTK OZA 116 M10.

After a bit of investigation I decided to swap over the connectors. (I'm hoping the M10/M8 designation only refers to the plug shape). I cut and resoldered the 4 wires. (That isn't as easy as it sounds with a small iron. You really have to pre-heat and tin each wire first). And I smothered the joints with hot glue to make sure there would be no shorts.

So far the sensor seems fine in the car. No 'check engine' issues. If anything its marginally smoother, but that could be my imagination. The big test will be next week when I do a 700km country trip. I've done the same trip more than 100 times so I should be able to feel any difference and see it in the fuel figures. I'll let you know.

(I should point out that the orginal equipment NGK sensor that came out of the Magna and the sensor that I put back in it looked identical. But they were both distinctly different to the Bosch sensor you linked to. The NGK sensors had slotted holes in the probe. Dunno if that makes any difference).

thanks for the info alchemysa, it did help.

after many hours of swearing, yelling in multiple languages, and rolling around under the car.. i managed to remove the old sensor.. Man !! it just did NOT want to give up...
The Bosch sensor fit in fine, and color codes were the same, the wires are made of some strange metal probably tin and mixture of stuff, it just wont accept solder... variety of methods failed, i was unable to go and buy any other type of solder so i went the old way, just twist tied them, and shrink wrapped on top.

2 years ago My best fuel values were 100kmh highway, 5.4-5.8 without aircon, 6.4-6.6 with aircon.
recently this number was up to 7,4 - 7.9 with aircon (don't remember without aircon,, been too hot this year)

after i replaced the sensor, highway values became 6.1 without aircon, and 6,6 - 6,8 with aircon. which is better than before, but not as good as what it used to be.

I don't know whether the sensor type is not the perfect one, or whether a new sensor needs some time to break in, or maybe a battery reset is necessary or maybe tire pressure was different back then, or there are other elements aged or changed in the engine ever since.

i will keep an eye on things, and update the thread if i notice anything worthy of sharing.

BTW, i saved many hundreds of bucks within the past few years with the help and information i got from this forum. As a complete car noob, i was able to learn how to fix and do some stuff..
i will be more than happy to donate what i can every now and then if such thing exists. can someone point me in the right direction please.

The Bosch sensor fit in fine, and color codes were the same, the wires are made of some strange metal probably tin and mixture of stuff, it just wont accept solder... variety of methods failed, i was unable to go and buy any other type of solder so i went the old way, just twist tied them, and shrink wrapped on top.


Vaguely remember soldering wires anywhere near the sensor is a big no-no, something about lead migrating down the wires and ruining the sensor?

The wiring is made of stainless steel, so Google tells me.
Bosch says to not solder them.

Someone else may be able to shed some light on this.

i managed to remove the old sensor.. Man !! it just did NOT want to give up... ...., it just wont accept solder... .

Yep hard to get anything out that has been baked by hot exhaust temps for years, the sensors are very easily destroyed by applying voltages, a multimeter is a quick kill, but they also warn of stray currents from soldering irons, so hopefully you had a good earthed iron - the temp of the soldering should not be a drama.

2 years ago My best fuel values were 100kmh highway, 5.4-5.8 without aircon, 6.4-6.6 with aircon.
recently this number was up to 7,4 - 7.9 with aircon (don't remember without aircon,, been too hot this year)

I hear about figures like this occasionally but must admit I am dubious about the accuracy. If true they are pretty amazing I think. Even brand new 2 litre cars arent delivering much better than that. How do you determine it? I've always worked it out by recording mileage and litres to top up the tank. And I usually base it on 3 or 4 fill ups. I dont think I ever got anywhere near your original figures even when the car was pretty new. The last very long highway trip, before the sensor, was nearly 10 litres per 100 ks. A recent long trip after the new sensor was probably a bit better but not much.

(Edit) I should admit that my country highway driving is almost always at 112 to 115kph. The extra few kph (over 100) does drink up the juice.

I hear about figures like this occasionally but must admit I am dubious about the accuracy. If true they are pretty amazing I think. Even brand new 2 litre cars arent delivering much better than that. How do you determine it? I've always worked it out by recording mileage and litres to top up the tank. And I usually base it on 3 or 4 fill ups. I dont think I ever got anywhere near your original figures even when the car was pretty new. The last very long highway trip, before the sensor, was nearly 10 litres per 100 ks. A recent long trip after the new sensor was probably a bit better but not much.

(Edit) I should admit that my country highway driving is almost always at 112 to 115ks. The extra few kph (over 100) does drink up the juice.

Magnas seem to vary a lot in their open road fuel consumption, for some reason. Best I can do is 7.7L/100 km in my TJ on a 300 km open road trip.

As for modern 2L cars - yes, pretty much the same fuel consumption on the open road, still need the same KW to push the car though the air, maybe 1 or 2 L less due to less friction inside the engine. But what they can also do, is get something similar around town, where the Magna suffers greatly from stop/start traffic. The v6 just isn't working in it's most efficient rev range around town, whereas a 2L with variable valve timing is.

What you have to remember is that the Magna is a heavy car (1500kg), but has good aerodynamics. On a flat highway it will get better economy than a 4cyl car due to the low wind resistance. The weight does not matter as it is not climbing hills or accelerating/braking. Around town you can get good economy if you drive in such a manner that you rarely use the brakes. This means coming off the accelerator early so the car slows down naturally due to wind/rolling resistance. Stepping on the brakes just converts your kinectic energy into heat, if you let the car slow by itself you may roll 500m extra for free. This quickly adds up to many extra kilometers for the same amount of fuel.

For what its worth;
I'm not surprised at the difficulty of soldering the O2 sensor leads. Due to the sensor sitting in the hot exhaust, a copper wire would oxidise to copper oxide quickly,
High temperature wiring (also used for the element connections on electric stove elements) has some (nickel/chromium?) added and makes soldering difficult. Often the connections to this kind of conductor is by crimping or welding a termination to the leadwire. Part of the trick to minimise the transmission of heat to the terminations from the sensor, is to use a long length of the lead wire. The insulation material of the wire would likely be a high temperature material too and possibly a flourinated material. Normal polythene materials or PVC would be inadequate and this rules out normal sort of heatshrink sleeving.
hope this helps.

Stepping on the brakes just converts your kinectic energy into heat, if you let the car slow by itself you may roll 500m extra for free. This quickly adds up to many extra kilometers for the same amount of fuel.

I'm no physicist but this bit about converting kinetic energy to heat sounds a bit 'over analyzed' to me. If you drive that last 500 metres at 2000 rpm then slam on the brakes then yes you are going to use more petrol to get you over that distance compared to rolling there (using kinetic energy) at 500 rpm. But the fuel saving comes about simply because you are using less petrol at lower revs. At 2000 rpm you use more petrol over that last 500 metres because you are converting petrol into power, not because at the last second you are converting kinetic energy (the momentum of the car) into heat.

I hear about figures like this occasionally but must admit I am dubious about the accuracy. If true they are pretty amazing I think. Even brand new 2 litre cars arent delivering much better than that. How do you determine it? I've always worked it out by recording mileage and litres to top up the tank. And I usually base it on 3 or 4 fill ups. I dont think I ever got anywhere near your original figures even when the car was pretty new. The last very long highway trip, before the sensor, was nearly 10 litres per 100 ks. A recent long trip after the new sensor was probably a bit better but not much.

(Edit) I should admit that my country highway driving is almost always at 112 to 115kph. The extra few kph (over 100) does drink up the juice.

those figures i give wouldn't really be accurate where long distance driving is considered. i basically use the same route of 7-8kms on motorway, towards the same direction just to get an idea of what's happening with the fuel economy.
the slope of the road, the wind strength and direction as well as who is driving around me would of course impact the consumption.

what got me start scratching my head about fuel was, coming back after an overseas trip where car was parked for two and a half months, and suddenly realizing i was getting under 500kms per tank within my daily routine, which is mostly city driving and pretty much same distances. i generally got 550-600 , but began getting 450, 480ish, once i got under 400 which caused a jaw drop..

i did a longish trip this weekend, from gold coast to coffs harbour, thru highway hills up and down, and got an average of 9 liter per 100 , which actually meets the general specs around, but i am still not impressed. i know this car did better, and drove better before. I am just trying to go back to what it was before.

i think the new sensor isn't doing the job right. if you remember mentioning how they have tip slotted or side slotted types, i guess thats where it matters unless i somehow buggered the wires while installing the new one on.
i am just ordering the actual right part (i hope they post what i order correctly this time) and will again be bothered to install it and see what happens.

as for other comments,
i don't find magna's as heavy cars. 1370kgs Curb weight given for third gens (resource wiki) , thinking that is with a full 70liter tank, i'd say its impressive for a car of such size and 3.5 liter engine. A mate of mine has a small arse Golf that weights about 1300 ...

i think what makes magna's fuel efficient on highways, is the good torque and kw of engine, and good gear ratios. it just doesn't have to shift down and rpm up so frequently to climb and accelerate like some cars do, and i think a steady 2000 rpm doesn't require much juice to run.

i think what makes magna's fuel efficient on highways, is the good torque and kw of engine, and good gear ratios. it just doesn't have to shift down and rpm up so frequently to climb and accelerate like some cars do, and i think a steady 2000 rpm doesn't require much juice to run.

Agreed. It seems to be able to go up most hills on the highway without shifting down. With a full car load it has to shift down to maintain speed. If it had a 6sp gearbox it could rev a lot lower to reduce throttling and frictional losses, however the cars I've driven with a 6sp will shift down when you want to accelerate just a bit such as going up a little hill, it gets annoying after a while.

The fact that it is FWD and has low wind resistance helps a lot as well.