Outer Limits 4x4 Board

I have a 95 DOHC 3500 import pajero, it has an oxygen sensor in exhaust in the normal position on the motor side of the cat convertor. It also has another sensor in the rear of the cat convertor (looks like a smaller oxygen sensor), does anyone know what the second one is for? I am going to change the factory convertor for a high flow one but are not sure what the second sensor does. I'm guessing I will have to weld a socket on the new cat to take the sensor.

Also does anyone have a SWB J top 3500 rear tailshaft laying around? The one with the CV joint at the front rather than a universal joint. The dust boot is stuffed on mine and Mitsubishi claims that a whole new tailshaft is needed, have tried driveline services and such an they say they can't refit a boot but that they can cut the CV off and fit a uni joint.

Thanks.........

I have no cat in my exhaust and just left the sensor plugged in but tied it up out of the way.

No idea what it does.

I'd suggest you will want to keep the CV joint rather than go to a uni - they put them there for a reason, expecially if your paj has a lift. All of the movement in the rear is at the front joint due to the angle of the rear diff, so a uni in there would make vibrations.

It is basically so your computer can verify that your converter is working properly, by comparing readings from the first O2 to readings from the 2nd one. If you are putting a high flow cat in and you reinstall the 2nd O2 it should be fine, but if you are all together removing your converter your check engine light will come on. There are various ways to fool the computer though, there are recessed bungs that bring the O2 sensor out of direct exhaut flow as well as other methods to "fudge" the readings.

NJV6 wrote:I have no cat in my exhaust and just left the sensor plugged in but tied it up out of the way.

No idea what it does.

I'd suggest you will want to keep the CV joint rather than go to a uni - they put them there for a reason, expecially if your paj has a lift. All of the movement in the rear is at the front joint due to the angle of the rear diff, so a uni in there would make vibrations.

NJV6 does your engine light come on like Mephisto explained? Also I want to keep the CV jointed tailshaft, my car doesn't have much of a lift but the CV setup is really strong and I don't want to mess with that.

I have had a driveshaft CV boot installed by driveline services to keep dirt out and grease in but it is stuffed again in 4 races (That was a standard CV boot, a lot weaker than the original mitsi boot with pressed steel retainers). Options are cut CV off and fit uni, buy brand new tailshaft from mitsi for quite a lot of $$$$, or search for a second hand one.

No, my check engine light does not come on.

My sensor is simply unbolted from the cat and zip tied to something, still plugged into its wiring! Its probably measuring fresh air oxy levels!

I don't think it has effected the computer - it still goes ok, maybe it could go better!!!

I'll unplug it one day and see if it alters!