O2 sensor whoops, help needed

[bikerjosh]

:cry2:Ordered a replacement O2 sensor before pulling current one. Yeah I know, but I was at work and wanted it to be at my place by the weekend.
This is a single O2 model originally sold outside CA, running a SC, URD 7th, and 2.2 pulley.

Ordered a Denso 234-4162(BTW- 2 bolt flange, 4 wire/4prong harness), to replace my one O2. My old one looks different, threaded flange, 5 wires /6 prong plug, and different tip.
Wires are white, red, grey, black, & yellow.
Any idea what model number I need?

Here's a pic.

Thanks Josh

 

[bikerjosh]

here's a picture of both side by side, original one also has a longer wire harness.

Thanks

 

[TheDurk]

Wow. First, the '98's were definitely flange type sensors so your exhaust has been redone--maybe upsized from stock when they did the S/C. Is this the upstream sensor (bank 1 sensor 1) or downstream (bank 1 sensor 2)?

Also, Cali. and Federal exhaust emissions setups were the same in '98, only evaporative emissions were tougher in Cali., so that is not an issue. The plug on your old one looks like nothing I have seen before on a 4Runner. All 4Runner sensors I have seen have only four wires, not five. How many wires on the harness side and what are the colors? Were they spliced upstream from the harness plug?

I am thinking that a new threaded-type exhaust bung was installed on your rig. Some non-Toyota o2 sensor was installed in that bung and a new harness plug was spliced into the original wiring. That sensor of yours could come from anything.

My only suggestion is that maybe a universal downstream O2 sensor for an '01-'02 might work. The upstream sensors for those years are wideband A/F sensors and will not work with a '98 system. But the downstream sensors should work in both the upstream and downstream positions on a '98 if you can decode the wiring colors by looking at the harness upstream from the
connector. Since you will be splicing on to your old sensor plug, you will have no trouble matching the length.

That would be a Denso 234-4209. It looks like this:

I think that is as close as you will come in a Toyota sensor, but it is still a different tip than yours.

Amazon.com: Denso 234-4209 Universal Oxygen Sensor (Air and Fuel Ratio Sensor): Automotive

Your sensor looks like this Bosch that fits a 2002:

I am really guessing here, but that sensor just doesn't belong on your truck. I have no way of knowing if the '02 4Runner threaded sensor is compatible with the threaded bung on your truck. But if it isn't, the only other thing I can think of is to take your old one down to NAPA or other FLAPS (Friendly Local Auto Parts Store) and find somebody over thirty who will try to match it for you. The under-thirties will just stare at you and ask "What's it for?" with their fingers on the keyboard (in my experience, anyway).

When you said single O2 model did you mean single cat? Because all '98's, indeed all third gens have two O2 sensors, before and after the cat or cats. Unless you have a non-US build. As far as I know, all OBDII compliant vehicles have 2 sensors and all US 3G 4Runners are OBDII.

 

[bikerjosh]

Wow. First, the '98's were definitely flange type sensors so your exhaust has been redone--maybe upsized from stock when they did the S/C. Is this the upstream sensor (bank 1 sensor 1) or downstream (bank 1 sensor 2)?

Thanks for the response, yeah should have mentioned, that the exhaust was redone by the PO, magna flow cat and muffler.
Only one cat, one O2 sensor before/upstream cat (this is the one in question) and a traditional looking one post/downstream of cat.
By traditional, I just mean it looks like the correct one that the website calls for.
sorry for the lack of info.
Thanks Josh

 

[TheDurk]

Thanks for the response, yeah should have mentioned, that the exhaust was redone by the PO, magna flow cat and muffler.
Only one cat, one O2 sensor before/upstream cat (this is the one in question) and a traditional looking one post/downstream of cat.
By traditional, I just mean it looks like the correct one that the website calls for.
sorry for the lack of info.
Thanks Josh

OK, so I bet that front o2 is a bosch sensor for a Honda or something. A really good parts guy might recognize that plug and fix you up. Or get the universal and try to match the wiring if you can find the four original Toyota wires on the truck side of the connector and match the colors. Or find the guy who did it and ask what the heck he put in there. Good luck.

 

[TheDurk]

I may have found a match. It LOOKS right, and has 5-wires and six prongs. It is definitely NOT Toyota technolgy, but is used with aftermarket special EFI controllers from AEM. Is it possible you have a custom EFI set-up on this rig that uses a wideband controller (not seen on 4Runners until the '99 Cali. rigs)?

Take a look:Home » Shop » Wideband O2 » O2 Sensors » Alternate Bosch LSU Wideband O2 Sensor ( UEGO ) for AEM Wideband UEGO ( all types ) [ 30-2001 ] and FAST Air/Fuel Meter [ 170408 ] and Dynojet Wideband Commander [ 48292001 ] and GM [ 12575657 ] and Bigstuff3

Here's another off eBay:Linky

or, from AEM:Linky

If you do have a custom EFI set-up, all bets are off. Just try and match what's on there or find out what is in fact on your truck and what it needs.

 

[bikerjosh]

Ding, ding ding.We have a winner, thanks theDurk. I must have been out in the garage when you posted this.
Yep, I discovered what I have is a Bosch lsu4.2 wideband O2 sensor p/n 0258007206, off to the auto parts store.
Hopefully this will be the final part I'll be replacing so I can smog this dang thing and start tearing it apart. :driving:
thanks Josh