SIKHILUXSURF
New member
Where did you mount your wideband o2 sensors? i know it is said to be mounted before the cats and after the collectors merge but there isnt a whole lot of room to be honest. i just need some pictures for ideas.

I'm a 3RZ guy, but mine is just upstream of the primary O2 sensor. Taking a look at the 5VZ headers either just before or adjacent to the factory sensor looks like the best bet assuming clearance is there. Pic below is from TW and a first gen Tacoma, but I'd assume positioning would be similar if not identical on a 4Runner, although I'd weld the wideband bung in a bit more towards the top of the pipe than in the photo to avoid fouling of the sensor.
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I had mine mounted between the transmission pan & the downpipe. I have headers on there now but I can get a photo tomorrow. I had a shop do it since it was way easier to weld up on a lift by a professional, rather than a hack-job by me.
Reviving this for a quick question - where did folks run the wire to the sensor? Did you come down and out near the tranny or through the firewall and down/around?
I'm figuring I'll go down next to the shifter, but thought I'd ask...
Bumping this old thread in hopes of an answer to this exact question. Also what's a good power source if I'm going to put an afr gauge near the cubby underneath the cigarette lighter, can I just tap into the 12 volt right there with the cigarette lighter?
I'm installing my afr gauge and was curious if you could tell me which wires you tapped into? More specifically where the ignition wires are that you hooked it up to?Yeah, through the firewall is the easiest, I ran mine through the ECU harness boot. Cables are nice and long.
I tapped a switched power source coming from the ignition wires, so it's only on when the key is on the "On" position. Didn't want any parasitic draws happening.
Isn't it even easier to just to read it off of OBD2 with a scangauge?
The AFR reading? From all my research, only certain years have a reading on afr and even on those years are not accurate enough to have any use. Correct me if I'm wrong, but if you want to get an accurate AFR reading you need to install a wide-band kit, regardless of the year for 3rd gen 4runners.
Are you running a supercharger with a different tune? Otherwise I'm not even sure why you would need an AFR reading in these 4runners...
Isn't it even easier to just to read it off of OBD2 with a scangauge?