Outer Limits 4x4 Board

Since replacing my cracked exhaust manifold with a set of extractors I have not been able to remove the O2 sensor from the old manifold. I was told to drive with no O2 sensor wouldn't harm the car, so the welded nut on the new extractors ready for a O2 sensor has not had one since it was installed.

The fuel economy has not been all that wonderful lately and also twice on one trip the Check Engine light came on. After each time I stopped the car and restarted it and the light went away. I suspect because turning the car off reset all of the ecu codes. Both times the check engine light came on, we were doing 110 along a freeway, whereas around town and out 4wding I have not seen the light come on at all.

Is the lack of O2 sensor the cause of my slightly poorer fuel economy and the reason why the Check Engine light comes on when I'm at speed?

Cheers

Goldey

Good luck getting it out. exhaust shop here used a vice and vicegrips and it came out at last, try some heat on there.

with the nut, does your ones have the hole punched out to fit it through or still plated up.

Btw, i would say a possible yes it could cause these problems

Nic

Thks Nic

Yes the extractor O2 fitting has a hole where the nut is welded on, so no worries there.

I have used copious amounts of WD40, penetrene and both a tube spanner (slightly modified to fit, but ended up stuffing it) and a 21mm open ended spanner that is now VERY open ended if you know what I mean. I haven't tried heat, maybe I'll give that a go. But if I end up using heat to get it out, I'm thinking there's a good chance that will bugger the sensor anyway.

Been quoted two prices so far on a new sensor. Genuine one I can get for $240 I think it was, and an aftermarket jobby from Repco for $80. I think I may be up for another 80 bucks out of pocket pretty soon.

Cheers
Goldey

Cold chisel and FBH.

Belt into the manifold on the casting line alongside the sensor. It should almost split in half - then a few belts in the appropriate places to finish the job off.
Took me all of ten minutes

I've just swapped one of the sensors on the V6. I used a universal sensor and on the first tank the consumption was still pretty terrible but the second tank was about 3l/100km better. Be interested to see if the third gets any better.

Hi, I have done the same thing, But I finally got mine off without rounding the nut part too badly. I just used lots of CRC (I guess you lot call it WD40) and a ring spanner, which I hit many times with a hammer.

But I would recommend heat, but try to heat the manifold more than the sensor (I think). But as long as you aren't melting the wires, the sensor can take it, they are designed to work when hot anyway.

Here is a link to testing the sensor once it is out, if you wanna test it.

http://www.mr2.com/TEXT/O2_Sensor.html

Btw, it is a four wire sensor right?

I wanted to use my four wire sensor to check my air fuel ratios, but the signal was coming out really oddly, so I just bought another universal sensor (single wire) and welded a new nut onto my extractors. I haven't tried using the universal as the engine's O2 sensor though.

cj wrote:I've just swapped one of the sensors on the V6. I used a universal sensor and on the first tank the consumption was still pretty terrible but the second tank was about 3l/100km better. Be interested to see if the third gets any better.

After a couple more fills it is still 3l/100km better and the check engine light has not been seen since I used a universal 4 wire sensor from Bosch.