Topic: O2 sensor location ?

[Cheesemaker]

As most of the OG know, I have a second gen toyota 22re.  And the O2 sensor is in the exhaust manifold.  Now I'm having issues with the stock exhaust flange nuts staying tight.  Eventually, they will start to back off and I get this tinny rattle sound.  And low and behold the nuts are backing off.  And this is with new Toyota crimped nuts.  I have a header that I got off a member here, but it came off a 3rd gen 22re, with the O2 sensor located right before the cat flange.

So, here is my dilemma.  Does the O2 sensor have to be in the stock/near stock locations for specific models?  IE, 2nd gen and 3rd gen. 

I don't have to smog, so I'm not worried about that.  But my concern is, if I put on the header that is designed for a 3rd gen on my truck, will it have adverse affects? 

I'm kinda thinking that it might.  ECM programming, exhaust temp difference in two different locations, and so on. 





Or should I just loctite the snot out of the studs the next time I have to tighten the nuts up? 

[junya92toy]

Try some safety wire too

[Wainiha]

Interesting question about the O2.  I would geuss a few inches foward or back would not affect the gases it reads unless you had and upstream leak.

Temperature could be affected.  But I don't see it being a problem.

But then, all I do around here,  is guess....

[emsvitil]

If you don't already have a heated sensor retrofit a 3 or 4 wire heated sensor and you won't have any problems with O2 sensor location.   Run the heater off an ignition + source of power.

Have you tried jam nuts?  (I do that on my exhaust and they never get loose)

[OOPS]

If you do not have this clamp on your down pipe the exhaust has a tendency to work loose.

[Snowtoy]

The O2 system can be sensitive to changes in length of the wire, and is why most have issues with the universal aftermarket sensors when they splice them into the factory harness.  It would probably be better to weld an O2 bung onto one of the down pipes and keep the current O2 sensor in the same place.

If you haven't seen them, Stage8 Fasteners are supposed to put an end to bolts coming loose.

[emsvitil]

If you do not have this clamp on your down pipe the exhaust has a tendency to work loose.

I was cracking my downpipe every 3-5 years where the 2 pipes merged into 1  until I did this additional step..

Loosen the 2 bolts (just enough so you can move the bracket) that hold the bracket to the bellhousing.

Tighten the clamp on the downpipe.

Tighten the 2 bolts on the bellhousing

[Cheesemaker [OP]]

I wasn't able to reuse the bracket I had on my truck, cause it originally was a turbo motor.  So, the one that came with my truck wouldn't work with the 22re exhaust.  So, I need to source one up now!  And with the exhaust flexing, and no bracing, definitely explains why it keeps working loose!  The nuts I'm using are the Toyota exhaust flange nuts, and are crimped.

[HogCanyonHopper]

I have the clamp and bracket. Let me know if you want it. I will send it to ya 

[Cheesemaker [OP]]

PM on the way Hog.